We most often use the adverbs “already”, “just”, “still” and “yet” with the present perfect, although they may be used with other verb tenses. These adverbs make reference to time and their location within the sentence depends on which of them we are using.
“Already” refers to something that happened before or sooner than expected and generally is located between the auxiliary verb and the principal verb.
“Just” is used for actions or events that occurred shortly before or not long ago and like “already”, “just” is located either before the principal verb or between the auxiliary verb and the principal verb.
We use “still” for actions or events that have not happened or have not ended, especially when we expect the actions or events to have happened sooner. “Still” is frequently used with other verb tenses, but regardless of the verb tense, this adverb is always found before the principal verb.
“Yet” is used for something we expected to have happened but has still not happened. We tend to use this adverb in negative and interrogative sentences. In contrast to the other adverbs discussed here, “yet” is generally found at the end of the sentence.