Question

F. When Since/For is used in Past Perfect Continuous Tense ​

Answer 1

Answer:

Before the words, the past perfect continuous tense.

This is the time when it is used.

Answer 2

Explanation:

part perfect continuous tense example is:-

she had been studying.

now basically ur qus is when to use since and when to use for

so since is used for taking an approximate time value like: since morning, since afternoon, since evening, etc

and for is used for a definite time like 3 hours, 4 hours and so on.

so let's try it in the same example taken above

=*she had been studying since morning*. (we do not know for how much time she has been studying)

= *she had been studying for 3 hours. (we know that she has been studying for a specific time)

so this is the basic difference between since and for. hope it helps. please mark me as the brainliest.