If “I woke up at 10” is okay, what about “I slept at 10”?

Question

When did you wake up?

I woke up at 10.

But then if I say, “When did you sleep?”

I slept at 10. – seems difficult to digest!

That's because sleep is a process that includes duration.

I slept for 10 hours. – this way, it's digestible!

But when I mention the point of time, is it okay?

Strange thing is, if I'm describing my habit/routine, it's perfectly fine..

I sleep at/by 10

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I request not to take this question 'logically'. It's about English. Nobody is perfect in timing. Please don't argue that you cannot have 'perfect time' of sleeping because you don't know when you slept. I'm talking about the sentence structure and not precise timings.

By the way, “I slept at 10” is very common in India.

Answer 1

No, we would not say "I slept at 10". (AmE). Either say

• I was sleeping at 10. (this means you were also sleeping some before and after 10) or

• I {fell asleep/went to sleep} at 10. (means you were not sleeping before 10.)

Answer 2

You can't use 'wake' and 'sleep' in the same way because they have significantly different meanings.

'Wake' is specifically a transition from one state to another. When I wake, I stop sleeping and start being awake. This happens at a moment in time, so I can specify just one moment. "I woke at 10."

'Sleep' is an ongoing process. I start sleeping, sleep for a while, and then end. My sleeping didn't occur at any one point in time, so I can't say when it happened. I can however say when I started sleeping. "I fell asleep at 10."

This is why "I slept at 10" is ambiguous and confusing. I don't know what point in the sleeping process you're referring to. It sounds like you're just saying you were asleep at 10.

Common forms for this expression include

• "I fell asleep at 10"
• "I went to sleep at 10"
• "I went to bed at 10"

However, note that "going to bed" does not necessarily imply "going to sleep". I may go to bed at a point in time, engage in other activities such as reading, and then fall asleep at a later point in time.

If you wanted to say when you normally go to sleep, rather than when you went to sleep one particular time, then common phrases include:

• "I go to sleep at 10"
• "I'm asleep by 10"
• "My bedtime is at 10"

The most precise phrasing is the first. The second implies that you may sometimes fall asleep earlier than 10, and the third only refers to going to bed, which may or may not be when you go to sleep.

Sometimes other short activities - short meaning about an hour or less - can be referred to as if they took place at one particular moment, such as eating. It would be more common to say "I ate at 10" than "I started eating at 10", unless you were having a very long meal. If I take a short nap, I might even say "I napped at 10".

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Note on Definitions

Note that 'slept' is the simple past tense and past participle of 'sleep'. After checking Wiktionary, Merriam-Webster, and the Oxford Dictionaries, none of them have "start sleeping" as a listed meaning for 'sleep'.

On the other hand, 'woke' is the simple past tense and past participle of 'wake'. In all three sources, the definition for 'wake' means to "stop sleeping", as in this definition from Merriam-Webster:

to stop sleeping : to become awake after sleeping

Answer 3

As Brian has already said: "I was sleeping at 10" and "I fell asleep at 10" are correct.

However, I just want to add that, if you necessarily want to use "slept", "I slept from 10 (o'clock)" is correct too. This is usually followed by "to", for example: "I slept from 10 PM to 6 AM".

Answer 4

Here's what's going on: the primary meanings of the words "sleep" and "at" are slightly incompatible, but combining them leads some people to stretch them beyond their primary meanings in a reasonable way, and some people refuse to stretch them.

At

The primary sense of the word "at" is spatial: it mainly indicates a location without regard to its structure. You say "I am at work" or "I work at 10th St. and Main" when you just mean the location; you say "I am in the building" when you want to distinguish being inside or outside. My answer here gives more details. The main thing to notice is that "at" tends to suggest that you are regarding a location as a point in space even if really it's larger than that.

When you use "at" temporally, you're making an analogy with its spatial sense, so "at" tends to indicate a point in time. So, you say "My plane landed at 1:34" or "We're going to have a meeting at 9:00."

Stretching slept and at to make sense with each other

Sleeping usually takes a long time. It doesn't happen in an instant. But "at" suggests that you are talking about an instant. Strictly speaking, that's a contradiction. So, when you say "I slept at 10:00", a listener must stretch "sleep" and/or "at" in some way to make sense of the sentence.

Before I explain what happens, let's look at "We had a meeting at 9:00." A meeting, just like sleeping, also takes time. It doesn't happen in an instant. But no one is stupid or dogmatic enough to insist that you always say "a meeting from 9:00 until 10:00" or "a meeting starting at 9:00". No one interprets "a meeting at 9:00" to mean "a meeting that lasts only an instant, occurring at 9:00". People reasonably interpret "a meeting at 9:00" to mean "a meeting that starts at 9:00". Since "at" suggests a point in time, and a meeting extends for a range of time, you have to think of what would some reasonably mean by "a meeting at 9:00". Since usually you want to indicate when a meeting starts, so you can all arrive at the same time, you reasonably take "We had a meeting at 9:00" to mean "We had a meeting that started at 9:00".

When someone hears "I slept at 10:00", they are in the same position as when they hear "We had a meeting at 9:00", with two differences. (1) Using "at" with "sleep" is unfamiliar, so it might be a new stretch for them. (2) The verb "meet" does suggest an instant in time: the instant when you meet. It's hard to know exactly when you fall asleep, so the idea of a starting time for sleeping is not as salient. Whenever people talk about scheduling meetings, the start time becomes salient—that is, your mind is primed to easily put attention on the start time. Since we don't usually talk about the start time of sleep, it doesn't "jump out" as easily as the obvious meaning that you have in mind. A listener wonders if maybe you misspoke or if they misunderstood.

Dictionary-thumpers refuse

Some people are less willing than others to bend words beyond their usual limits. You've probably encountered a few people who, when you bend a word to communicate your meaning when no other word has a closer meaning, opens up a dictionary, points to the definition, says "You're wrong!", and proceeds to disprove, with ironclad logic, the absurd proposition that results when the dictionary definition is taken as what you meant.

That's crazy, and happily not very common, but the fact is, there is a wide range in people's willingness to reasonably stretch words beyond their primary meanings or the usual things they're accustomed to hearing them applied to. Some people go along with the reasonable stretch easily; some refuse to go along with it until it becomes familiar through other people's usage.

Describing a routine

So why is it less objectionable to say "I sleep at 10:00" when describing a daily routine?

I think there are two main factors here: when describing a routine, you usually treat each activity without regard to its structure, often mentioning only its start time; and a routine is a plan, not an actual event.

Wake up at 6:00 a.m., jog at 6:30, breakfast at 7:30, start work at 8:00, status meeting at 9:00, lunch at 12:00 p.m., resume work at 1:00, leave work at 5:00, dinner at 6:00, post to ELL at 7:00, and sleep at 10:00.

The succession of "at"s establishes that each time is the start time for an activity. "At" is appropriate because the schedule doesn't describe what happens inside each activity. So, a reader is less likely to notice that "sleep at" would be unusual in other contexts. Proximity agreement is another situation where people often don't notice that a norm has been violated, because some other, more-salient factor drowns it out.

But probably the more important factor here is that a routine is a plan, not an actual series of events. A plan is an idealization, which exists only in your mind. So, in your mind, as you plan out your routine, you imagine that you start sleeping at precisely 10:00, just as your meeting starts at precisely 9:00. In an idealization, you think of activities as starting at precise, known points in time even though you know they won't go exactly like that in reality. That makes "at" a very good fit. But if you say "Last night, I slept at 10:00", this sounds strange because it suggests that you know precisely when you fell asleep, and in reality, that doesn't happen.

The grammatical principle

The grammatical principle here is that grammatical rules can't explain what's going on with an unusual use of a preposition as in "I slept at 10:00". Meaningfulness and grammaticality result from a hazy interaction between many factors:

• the primary meanings of the words

• the clash that results when they're combined

• the reasonableness or distance of the stretch from the words' primary meanings

• the salience of elements of the topic that make good, nearby targets for stretching the words

• the familiarity of the word combination or the manner of stretch

• the listener's ability and willingness to go along with the stretch

and one more thing, which I haven't mentioned yet:

• competition from other words.

When there is already another, familiar way to indicate the same meaning, people are usually less willing to go along with a stretch. Instead of "I slept at 10:00", you would ordinarily say "I fell asleep by 10:00" or "I went to bed at 10:00" because of that uncertainty about when you actually begin to sleep. Since there is another way to say what a listener thinks you probably mean, this is evidence that either you misspoke or the listener misunderstood—which is reason for a listener to be less willing to stretch "slept" to mean "started sleeping". To stretch a word beyond its usual limits, people usually want some need to be satisfied by that stretch: some aspect of communication to be served, which is not already well served by a familiar construction.

Answer 5

To sleep is usually understood to mean to be in the state of being asleep, not to fall asleep. Because sleeping is usually a long event (eight hours is commonly quoted), stating that you were asleep at a particular hour or a specific time makes little sense, unless you also state that you only slept for a short amount of time.

to sleep: to be in the state of being asleep

to fall asleep, to go to sleep: to change state from being awake to being asleep

to wake, to awaken: to change state from being asleep to being awake

to be awake: to be in the state of being awake

                awake             asleep
be in state     to be awake       to sleep
change state    to (a)wake(n)     to fall asleep

So sleep is not the opposite of wake. Asleep can be either an adjective or an adverb, sleep can be either a noun or a verb. I'm not aware of any single word verb for to fall asleep e.g: to go to sleep, to pass out, to lose consciousness, to become unconscious, etc. Here sleep and wake are used as verbs, while asleep and awake are used as adverbs with another verb to make it grammatically correct. Note the lack of symmetry!

When did you fall asleep? I fell asleep at 10 pm.

How long did you sleep (for)? I slept for eight hours.

When did you sleep? I slept from 10 pm till 6 am.

When did you sleep? I slept last night. (A long enough period of time to complete the process)

When did you sleep? I slept at 10, 11, 1 & 4 but I was awake the rest of the time.

In the sentence I ate at 10, eating usually takes less than an hour, so it is not saying that you were eating for exactly one minute at 10 o'clock but that you started eating at some time close to 10 and continued until you were finished a short time later, whether that took you five minutes or half an hour. Both I ate at 10 and I slept at 10 imply that you weren't doing the same activity at 9 o'clock or 11 o'clock.

Please note that Indian English uses words and meanings considered non-standard in other varieties of English such as prepone as an extension of postpone. It seems that these words and meanings crop up because Indians assume a symmetry in English that does not usually exist. They can be usually be understood without further explanation but cause initial surprise when encountered. Since you said that I slept at 10 is common in India, keep using it when speaking to Indians. Just be aware that not everyone outside of India will understand that you mean I fell asleep at 10. So most people will understand you even if they would not say it that way themselves.

It is to do with the amount of time it is expected for the activity to finish.

I drove to work at 8. I arrived at 8:30. I worked at 9. I slept at 10 but luckily I woke at 10:30 before the boss saw me at 11. I ate at 12.

drove - continuous, less than an hour is common

arrived - a single moment

worked - continuous, less than an hour is uncommon, up to eight hours is common, sometimes (a lot) more

slept - continuous, less than an hour is uncommon, eight hours is considered normal

woke - a single moment

saw - may be either a single moment or continuous depending on context

ate - continuous, less than an hour is common

Note that my story is very fragmented, and not just because it is using very short, simple sentences. It's not clear what I was doing between 8:30 and 10 except at 9 or between 10:30 and 12 except at 11 because I only said what I was doing at specific times. It is assumed that I was driving for half an hour and that I slept for half an hour because they are both continuous activities and the next event in the story concludes each of them.

Answer 6

I slept at 10.

This is grammatically correct, however, it sounds strange to my ears. But I don't think anyone would be confused hearing it in a conversation and would know what you were saying. If you are looking for an alternative, I would say something like:

I went to bed at 10.

Answer 7

I'm not sure what you're trying to convey. If you'd like a sentence with the same meaning as "I woke up at 10", you can say:

I slept until 10.

If you are trying to say that you began sleeping at 10, you could use either:

I went to sleep at 10.

I went to bed at 10.

If you are trying to say that at 10, you were asleep (not awake), you could use either:

I was sleeping at 10.

I was asleep at 10.

Answer 8

It's not incorrect grammatically, it's more of a logical issue. The amount of time you spend sleeping is usually arbitrary, unlike say eating or getting a haircut.

I ate at four. Sounds right because it conveys when you starting eating and one can reasonably estimate when you stopped eating.

I drove ate four. Only sounds right if you have some understanding of wear they were went. If you say just say "I drove at four", it sounds weird.

I baked at three, Sounds off unless you know what was baked.

I showered at three. Sounds right, because you can estimate how long it took.

Answer 9

The phrase "I woke up" refers to the point at which you began being awake, while the phrase "I slept" refers to the state of being asleep, but not specifically to its beginning. As others have already mentioned, you would say "I fell asleep" or "I went to sleep" to refer to the point at which you began sleeping.

But that's all really beside the point. The real problem with the statement "I slept at 10" is not the fact that it doesn't target the beginning of the act of sleeping. And, contrary to what you may read in some of the other posts and comments, it has nothing to do with the duration of a typical night's sleep relative to that of other activities. The real problem is, sleeping is not a process that typically has, or can have, a known start time.

Consider the following statements:

• "I ate at 11"
• "I work at 8"
• "My show is on at 7"

Almost all English speakers would be perfectly comfortable with those statements even though they refer to processes that vary widely in duration, and none of them explicitly target the beginning of a process. They are accepted because they all deal with processes that tend to have easily identified start times. That's the general rule you need to follow. If you find yourself associating a start time with a process that normally doesn't have a known start time, then you probably need to stop and think about what process you're really talking about. In this particular case, if you replace "slept" with "was in bed", I don't think anyone will find your statement the least bit odd. That's because it's very common for a person to know what time they start being in bed each night.