Present Perfect Simple

S + have/has + past participle

• In an action that began in the past, but we don’t know exactly when.

Ex.:
- I have (already) been to London.
- Have you studied for the test?
- They haven’t finished their Christmas play (yet).

Expressions to use: Yet (end of the sentence in negative), ever,never, just, already (after the verb have/has), since, for,recently (begin of the sentence).