现在完成时和现在完成进行时的标志词？

现在完成时和现在完成进行时的标志词一样吗，比如in the past few years 可以用在现在完成进行时中吗
(Source: Zhihu)
(answered by: alexcwlin; edited by: Adam Lam)

Difference between Present Perfect Tense and Present Perfect Continuous Tense

The word “perfect” means “bringing something to completion”. This word is a bit misleading in the term “Present Perfect Continuous Tense” because the action is still continuing at present.

Note the following between the two tenses:

1.      In relation to the past, both tenses started in the past.

2.      In relation to the present, Present Perfect Tense has already been completed at present, but Present Perfect Continuous Tense is still continuing at present.

3.      You don’t need to mention time line for Present Perfect Tense. It was completed in some recent past point of time and no duration is involved. There is no need to point out the time of completion.

4.      A Present Perfect Continuous Tense deal with duration, which points out the action is still happening at present. The words “for” and “since” are often used with Present Perfect Continuous Tense.

Examples:

Present Perfect Tense

1.      I already have supper.

2.      She has done her part in this project.

3.      I have started a new job.

Present Perfect Continuous Tense

1.      I have been working in the present company since 2015.

2.      My wife and I have been exercising for 2 hours.

3.      My son has been working hard to finish his homework since 7 o’clock.

Difference between Present Perfect Tense and Simple Past Tense

Both tenses referred to actions that were completed in the past, but Present Perfect Tense do not specify time, but Simple Past Tense does.

Example:

Present Perfect Tense: John said, “I have finished supper already. What can I do for you?”

Simple Past Tense: John said, “I finished supper 20 minutes ago. What can I do for you?”