Form 6a. Adjectives and Adverbs. Joining sentences

For practicing:
http://esl.fis.edu/grammar/multi/adadv.htm;
https://www.usingenglish.com/quizzes/33.html;
http://www.cityu.edu.hk/elc/quiz/adjadv.htm;
http://a4esl.org/q/j/ck/mc-adjadv.html;
https://www.englisch-hilfen.de/en/exercises/adjectives_adverbs/adjective_adverb.htm;
https://www.englisch-hilfen.de/en/exercises/adjectives_adverbs/adjective_adverb2.htm;
https://www.proprofs.com/quiz-school/story.php?title=conjunctions--but-so-1;
http://a4esl.org/q/h/vm/m-sco01.html.

Form 6a. Modals2

For practicing:
https://www.tolearnenglish.com/exercises/exercise-english-2/exercise-english-87468.php;
http://www.focus.olsztyn.pl/en-modal-verbs-practice.html#.XKZMuvZuLDc;
https://www.tolearnenglish.com/exercises/exercise-english-2/exercise-english-97711.php;
https://www.english-4u.de/en/grammar-exercises/modal-verbs.htm;
https://www.english-4u.de/en/grammar-exercises/modal-verbs2.htm;
https://www.english-4u.de/en/grammar-exercises/modal-verbs3.htm;
https://www.english-4u.de/en/grammar-exercises/modal-verbs4.htm;
https://www.english-4u.de/en/grammar-exercises/modal-verbs5.htm;
https://www.english-4u.de/en/grammar-exercises/modal-verbs6.htm.

Form 6a. Adjectives and Adverbs. Joining sentences

For practicing Adjectives and Adverbs:
https://www.englisch-hilfen.de/en/exercises/adjectives_adverbs/adjective_adverb_on_ly.htm;
https://www.englisch-hilfen.de/en/exercises/adjectives_adverbs/adjective_adverb_on_ly2.htm;
https://www.englisch-hilfen.de/en/exercises/adjectives_adverbs/adjective_adverb.htm;
https://www.englisch-hilfen.de/en/exercises/adjectives_adverbs/adjective_adverb2.htm;
https://www.ego4u.com/en/cram-up/grammar/adjectives-adverbs/exercises;
https://www.myenglishpages.com/site_php_files/grammar-exercise-adjectives-adverbs.php;
https://www.perfect-english-grammar.com/adverbs-or-adjectives-exercise-1.html;
https://www.english-grammar.at/online_exercises/adjective_adverb/adjective_adverb_index.htm.
For practicing Joining sentences:
https://www.english-grammar.at/online_exercises/adjective_adverb/adjective_adverb_index.htm;
https://www.englishexercises.org/makeagame/viewgame.asp?id=1676;
https://www.bradleys-english-school.com/online/multiplechoice/conj.html;
http://learnenglishteens.britishcouncil.org/grammar/beginner-grammar/conjunctions-or-so-because-although.

Form 6a. Modals1

For practicing:https://www.tolearnenglish.com/exercises/exercise-english-2/exercise-english-55666.php;
http://www.servator.cat/eva/index_files/Grammar/2ndcycle/3rESO/should_must_2.htm;
https://www.englisch-hilfen.de/en/exercises/modals/must_not.htm;
https://www.englisch-hilfen.de/en/exercises/modals/must_not2.htm;
https://elt.oup.com/student/solutions/elementary/grammar/grammar_05_022e?cc=lt&selLanguage=en;
https://learnenglish.britishcouncil.org/en/intermediate-grammar/modals-1;
https://www.learnenglishfeelgood.com/esl-mixed-modals1.html;
https://www.test-english.com/grammar-points/a2/have-to-dont-have-to-must-mustnt/;
https://www.englishexercises.org/makeagame/viewgame.asp?id=3023;
https://www.e-grammar.org/modal-verbs-can-may-must/test2-exercise2/.
Quiz:
https://www.tolearnenglish.com/exercises/exercise-english-2/exercise-english-87468.php.

Form 8b. Passive voice

For practicing:
https://www.englisch-hilfen.de/en/exercises/active_passive/active_or_passive1.htm;
https://www.englisch-hilfen.de/en/exercises/active_passive/active_or_passive2.htm;
https://www.englishgrammar.org/active-passive-voice-exercise-8/;
https://www.english-grammar.at/online_exercises/passive-voice/pa010-active-passive.htm;
https://www.english-grammar.at/online_exercises/passive-voice/pa007-active-passive.htm;
https://www.englisch-hilfen.de/en/exercises/active_passive/sentences_gaps.htm;
https://www.ego4u.com/en/cram-up/grammar/passive/exercises?06.
GRAMMAR QUIZ:
https://learnenglish100.com/passive-voice-quiz-english-online-exercises/.

Form 6b. Countable and uncountable nouns

For practicing:
https://www.myenglishpages.com/site_php_files/grammar-exercise-countable-uncountable-nouns.php;
https://www.english-4u.de/en/grammar-exercises/a-an-some.htm;
https://www.englisch-hilfen.de/en/exercises/confusing_words/few_little.htm;
https://elt.oup.com/student/solutions/preint/grammar/grammar_03_012e?cc=lt&selLanguage=en.
Homework exercises:
https://www.english-grammar.at/online_exercises/quantifiers/quantifiers1.htm
https://www.tolearnenglish.com/exercises/exercise-english-2/exercise-english-52605.php.

Form 6b. Present Perfect vs Past Simple

For practicing:

https://www.perfect-english-grammar.com/present-perfect-exercise-1.html;

https://www.perfect-english-grammar.com/present-perfect-exercise-2.html;

https://www.perfect-english-grammar.com/present-perfect-exercise-3.html;

https://www.perfect-english-grammar.com/present-perfect-exercise-4.html;

https://www.perfect-english-grammar.com/present-perfect-exercise-5.html;

https://www.perfect-english-grammar.com/past-simple-present-perfect-1.html;

https://www.perfect-english-grammar.com/past-simple-present-perfect-2.html;

https://www.perfect-english-grammar.com/past-simple-present-perfect-3.html.

Quiz:
https://www.englisch-hilfen.de/en/exercises/tenses/simple_past_present_perfect.htm.