1 https://www.codadi.com/guia-de-gramatica-inglesa/just-already-yet/ ( EXPLANATION IN SPANISH AND QUIZ AT THE BOTTOM)

2.https://elt.oup.com/student/englishfile/preint/a_grammar/file04/grammar04_b01?cc=global&selLanguage=en

3. https://www.superprof.es/apuntes/idiomas/ingles/gramatica-inglesa/verb-tense/exercises-present-perfect-simple-yet-already-just.html.

4.http://www.servator.cat/eva/index_files/Grammar/2ndcycle/4tESO/prsperf2.htm