Does present perfect continuous imply that the action/event is ongoing if the duration is given?

Question

In my grammar book the following examples for present perfect continuous (PPC) are given:

Example no. 1:

Is it raining?
No, but the ground is wet.
It's been raining. ( = It has been ... )

In this example, it is not raining any longer at the present moment.

Example no. 2:

It began raining two hours ago and it is still raining now.
How long has it been raining?
It has been raining for two hours.

In this example, it is still raining at the present moment.

Are these combinations, namely

• PPC without a duration => no more raining,
• PPC with a duration => still raining,

just coincidences?

Or does a given duration imply that the action/event is still ongoing, whereas an absent duration implies that the action/event is no more ongoing?

Or to put in examples. Are the following examples gramatically still valid?

Example no. 1*:

Is it raining?
No, but the ground is wet.
It has been raining for two hours.

In this example, it is not raining any longer at the present moment.

Example no. 2*:

It began raining two hours ago and it is still raining now.
Has it been raining?
Yes, it's been raining.

Answer 1

It seems that this depends more on context and expectation than grammar. For example, your sentence:

It has been raining for two hours

contains no information whether it is raining at this moment. However, it makes little logical sense why I would fail to mention that it stopped raining, so the sentence certainly implies (but does not require) that it is still raining.

Of course this depends on personal opinion. You could be mistaken:

A: It's been raining all day.
B: Is it still raining? When did you last check?
A: About ten minutes ago. Let me check again -- oh, wait, it's stopped now.

Because the nature of the past perfect continuous is to describe ongoing situation, it feels incomplete not to include some kind of qualifier to explain the time frame:

It has been raining, but I think it'll stop some time in the next hour.

It has been raining, so we're going to have to postpone the ceremony until tomorrow.

And so on. Again, context tells us whether it is still raining, or whether that information is important.

(Edit) In your first example, "It's been raining" actually means "It rained (at some point)". There's no reason to use the present perfect continuous, since it's obvious it's not currently raining, and we don't know when or how long it rained in the past.

Nevertheless, native speakers do say this kind of thing. I think it's odd, but not enough that I would correct anyone who said it.

Answer 2

Whether the action is ongoing depends on the meaning of ongoing.

It's been raining heavily all month.

It might not be raining at this moment, but the rain has been heavy throughout the month, and in the time-frame of the month the rain has been ongoing or continuous.

It has been raining heavily all day.

It might not be raining at this moment, but the rain has been heavy throughout the day, and in the time-frame of the day the rain has been ongoing or continuous.

The speaker's sense of the present is more like a penumbra than a stopwatch.

It has been raining heavily for two hours.

For a two-hour period that encroaches upon the speaker's present, there has been heavy rain. The rain might have stopped. It might still be raining.

It has been raining heavily for two hours. I wish it would stop.

It has been raining heavily for two hours. I'm glad that it has stopped.

Answer 3

Present Perfect and these examples:

Example 1

Is it raining?

No, but the ground is wet. It has been raining for two hours.

|It has been raining| should be: It rained for two hours.

The reason is this: If it is not raining now, you would not say it has been raining for two hours. You would only say that if it is still raining.

One of the rules for PP is that the state or condition continues to be true at the time of speaking. If the condition or state is no longer true, you don't use PP.

Is it raining? Yes, it is. It's been raining for two hours. [the rain continues] :p>Also, it is not even necessary to mention duration: Is it raining? Yes, it's been raining [implication: and continues to rain now, and there is no time given at all]

Example 2: It began raining two hours ago and it is still raining now. Has it been raining? Yes, it's been raining.

So, to summarize:

If a thing continues to be true at the time of speaking, you use PP. This is only one rule for the use of PP. And it is a big one. Of course, PP is often accompanied by an indication of the time as of which the action has been occurring: since yesterday, for [a week, hour etc.] but it does not have to be, as I showed above.

What determines, in the end, whether or not an action is ongoing depends on what the speaker wishes to say and the reality or unreality the speaker wishes to show and not whether a speaker puts in a phrase with for or since to indicate a time related to the action.

Here's a good exercise:

Question: "Have you been following my explanation" [i.e. until now when you and I are speaking].

Answer: "Yes, I have".

Question: "When did you last follow one of my explanations?"

Answer: "Not for a long time. I last tried to follow one of your explanations months ago."

And here we come to the other major rule about PP.

Either the action continues to be true or the particular point in time when it began is not relevant particularly. When it does become relevant, a native speaker will often switch over to the Simple Past to clarify an utterance and lock in a moment in time: last week, two months ago, etc. (but never since :)