UNIT 1: PRESENT PERFECT

Have or has?
Write affirmative sentences
Write negative sentences
Write questions 
Write the correct form of the main verb

http://www.ego4u.com/en/cram-up/grammar/present-perfect-simple/exercises?03 (HAS or HAVE)

http://www.ego4u.com/en/cram-up/grammar/present-perfect-simple/exercises?04 (AFFIRMATIVE)

http://www.ego4u.com/en/cram-up/grammar/present-perfect-simple/exercises?05 (NEGATIVE)

http://www.ego4u.com/en/cram-up/grammar/present-perfect-simple/exercises?07 (INTERROGATIVE)

http://www.ego4u.com/en/cram-up/grammar/present-perfect-simple/exercises?08 (ASK QUESTIONS)

http://www.ego4u.com/en/cram-up/grammar/present-perfect-simple/exercises (MIXED PRES. PERFECT)

PRESENT PERFECT TIME EXPRESSIONS

http://www.usingenglish.com/quizzes/122.html (YET/ALREADY)

http://www.adelescorner.org/grammar/pres_perfect/pres_perfect_yet.html (YET/ALREADY)

http://www.esl-lounge.com/student/grammar/2g7-just-yet-already.php (JUST/YET/ALREADY)

http://www.englishexercises.org/makeagame/viewgame.asp?id=1394 (FOR / SINCE)

http://www.ego4u.com/en/cram-up/vocabulary/since-for (FOR / SINCE)

http://www.grammarbank.com/since-vs-for-exercises.html (FOR / SINCE)

http://www.grammarbank.com/ever-never-just-already-yet.html (TIME EXPRESSIONS)