This is only an exercise in writing the present perfect progressive, (also called the present perfect continuous.)

Consequently you do not have to decide which tense to use, the correct form of the present perfect progressive is always correct. The verb is in brackets ( ) at the end of each sentence.

You can use contractions if you wish.('ve for "have", 's for "has") but only in the less formal sentences.

Here are some notes on its use:

There are some words never used with the progressive: ever never yet always: The present perfect is frequently used with these.

Sometimes the negative can't be used: e.g. "It has been raining for days." is OK but the negative could only logically be "It hasn't rained for days."

There are some verbs never used in the progressive: know, feel, hear, see, (except in colloquial uses like "He's been seeing Mary for months."

There are some verbs where the choice between present perfect and present perfect continuous doesn't make much difference, notably work and live:
"I've been working for the Post office for years."
"I've worked for the Post Office for years."