66

In math and computer programing, variables and constants (such as x and t in your examples) are treated like proper nouns (like names of people or places) rather than common nouns (names of a type of object). Just as you wouldn't say "I wonder what the Bob is doing today?" or "The Mary is coming over for dinner tonight." you also wouldn't ...


41

Of course in most contexts we use a to refer to a generic, non-specific example of some class (or the first mention of a specific member of that class), and the to refer to a specific previously-mentioned member of that class. This is not the case here. In this usage, both a and the can be used to describe an exemplary peasant, taking some random peasant in ...


28

"Post" in this sense is an uncountable or mass noun (as noted by Longman), so you'd always say "by post" (or "in the post", "via post" or "by mail"), never "by a post".


23

You are correct. If the mud has been explicitly mentioned, a subsequent mention should refer to the mud. This is also true if the mud can be easily understood from context. That seems to be the case here: it has rained, and the children are in a location where mud is likely to form. Even if the mud has not been mentioned, no one will be surprised if you ...


23

Some nouns like "apple" and "watermelon" are sometimes count nouns, and sometimes non-count nouns, depending on how we're thinking about them, not whether they're solid or broken. When we're thinking of individual pieces of fruit, "apple" and "watermelon" are count nouns: I have an apple in my lunch. We almost ate a ...


19

No, by here shows the method in use, how the action of sending documents is done - by post. It's an uncountable noun which refers to the public system for collecting and delivering of letters, so a post is never the case. Similarly, you can travel by train/car, you can pay by cheque, you can carry/ship goods by sea/air, you can read by candlelight. We use ...


17

"Slang" as a noun refers to the entire body of very informal language and terms, not just one word. So, we would say "it is a slang word", not "it is a slang". That would be like saying "It is an English" instead of "it is an English word" - English being the entire body of spoken language. As there are many ...


16

We can use the indefinite article (a peasant) if we are discussing an unknown peasant, or the definite article if we are discussing the generic peasant (considered as a type of person). Either is appropriate in the context you quoted.


14

There are some words in English where a single item uses a plural noun. Examples are:- scales (as you say) scissors trousers pants knickers tights Usually these are items where the original object has two or more parts (two pans for traditional balance scales, two blades for scissors, two legs for clothes worn below the waist). Over time (and in some ...


14

You need an article to avoid ambiguity. Meal as a substance means ground-up grains (e.g. oatmeal).


13

It’s a matter of context, and to a lesser extent jargon. A variable in mathematics actually has nothing to do with the symbol or name used to identify it. x² + y³ = 0 will always have the same solutions regardless of whether the variables are identified as x and y, Α and Β, or even ζ and Д. However, in any given form of an equation, the symbol or name used ...


11

In British English, although a 'pair (or set) of scales' is very common, we can say 'a scale'. This is a scale that I bought in the UK about 6 months ago from a well-known chain of supermarkets. It cost £8 ($11 US)


10

There's a distinction between "apples" (countable) and "apple" (uncountable). I'd say that there's a distinction between "apples" and "apple" in this context: if you say that the pie was made from apples, you're specifying that it was made from multiple apples - there's a pile of apples, and you used them to make the ...


9

It is normal to say "by post" in British English (or "by mail" in American English). You would never use an indefinite article with "post" in this context, since there is only one post ("a post" would therefore be a fence-post or similar). However, it can be correct to use a definite article, as in "through the ...


9

The dish is always called “apple pie“, and the main ingredients are: apple OR apples and sugar. Both the singular and the plural form are acceptable.


9

You could potentially use "you've got mirror all over the floor" as a humorous/slang-like expression ("you've got" in this sentence meaning "you have caused there to be"). As explained by other answers, it isn't grammatically correct English but it does have a comical aspect to it, perhaps even invoking surreal connotations (...


9

Either information or the information can be used. Use it without an article if you mean information generally. Use the information if you have specific information in mind, especially if you have already mentioned specific items of information.


8

As other answers have noted, neither is correct. You need She scored ... or She scores ... Although correct, these are awkward. In soccer/football you can say "she scored" but in this context I think the score belongs to the exam more than to the mathematician. So the sentence you want to replace is better: she had the highest score on the math ...


8

I think signal might be used as a mass noun by some communications technologists, but in normal English it is a singular count noun, and so needs an article in most circumstances. Here it needs the.


7

In both cases, you’re using ’peasant’ as a generic, but the generic forms are different in their meaning. A generic formed with the definite article in English is generally categorical. In other words, it talks about the noun as a category of person/place/thing/idea, describing all items referenced by that noun as one group. This is essentially the same as ...


6

Usage is changing over time in this context, which just goes to show that classifying nouns as "countable" or "uncountable" isn't always particularly useful... So far as I'm concerned, all three of OP's highlighted instances of past tense can validly be preceded by all three "articles" (that's to say, a, the and the "zero ...


6

Since you asked for a reputable source, I am going to begin in this answer with a reputable source and then move on to the specifics. What you are asking about is the usage of the definite article "the" alongside noun phrases (NP) structured around the preposition "of". "A of B" is an interesting structure, because you have a ...


6

"In the mud" is what you need in your sentence. "In mud" is possible for general statements as in ... playing in mud makes you happier! Playing in mud can make you healthier too. (Source) or generic descriptions of certain actions as in DRIVING IN MUD (also referred to as mud driving) or How to free a car stuck in mud


6

First, passenger means "somebody who travels in a vehicle but is not controlling that vehicle". It is incoherent to use "passenger" when there is no vehicle expressed or implied in the discourse. I suspect you mean "passer-by". Secondly, a singular count noun such as "passenger" can hardly ever be used without an ...


5

Stangdon's comment has the answer, but I'll enlarge it a bit. You're right that normally we use the when we expect the reader/hearer to know which thing(s) we are talking about, often because they have already been mentioned. So a possible way of starting the book could be: Alice was sitting on a bank by her sister, and was getting beginning to get very ...


5

Scales (meaning a balance or weighing machine) is usually plural: The scales are in the bathroom. When we want to refer to a single balance, we can say "a pair of scales", but I think most people would use that only for a traditional balance with two pans. The Oxford English Dictionary remarks of that meaning of scales "(†In 16th cent. ...


5

NO At least, not in the context you have provided. There is an idiomatic usage for putting "the" before a person's name, but it is usually used to clarify you are speaking about a specific person with that name. For example, I was on a flight one time and struck up a conversation with an elderly couple. I learned during the course of the ...


5

I sometimes hear articles in front of a variable name, if it’s to distinguish which of several possible assignments we mean. For example, if we have a sequence whose elements are a-sub-0, a-sub-1, and so on, I might specify “The a-sub-i minimizing the difference between a-sub-i squared and v,” or “an a-sub-j satisfying the inequality, ....” Afterwards, I ...


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