Comparatives and superlatives

https://www.ego4u.com/en/cram-up/grammar/adjectives-adverbs/adjectives/exercises

http://digitalcampus.free.fr/Level2/Unit22/SubUnit221/ComplSentQCM01.jqz.htm

http://www.english-grammar.at/online_exercises/adjective_adverb/ad032-adjectives-forms.htm


Too and enough

https://www.tolearnenglish.com/exercises/exercise-english-2/exercise-english-10731.php

https://elt.oup.com/student/solutions/preint/grammar/grammar_04_022e?cc=global&selLanguage=en


Irregular verbs

http://esl.fis.edu/grammar/verbs/5.htm

https://www.englisch-hilfen.de/en/exercises/irregular_verbs/crossword_8_10.htm

https://www.englisch-hilfen.de/en/exercises/irregular_verbs/mix.htm

https://www.englisch-hilfen.de/en/exercises/irregular_verbs/mix2.htm

https://www.englisch-hilfen.de/en/exercises/irregular_verbs/mix3.htm

https://www.englisch-hilfen.de/en/exercises/irregular_verbs/mix4.htm

https://www.englisch-hilfen.de/en/exercises/verbs1/index.php