Verbal Tenses ex. Page including gr. explanations and ex. for all verbal tenses; very useful for practice and revision:

http://www.englishpage.com/verbpage/pastperfect.html

Exercises with MUST

http://www.englishpage.com/modals/must.html

Past Simple and Present Perfect exercises. Choose the best option

Past Simple and Present Perfect exercises

Past Simple and Past Continuous exercises. Choose the right tense.

Past Simple and Past Continuous exercises

Reported Speech exercises

although-despite-and-reported-speech-ex.doc

Grammar exercises for the correct use of modals

http://www.englishpage.com/grammar/Modal_Verbs/Exercises/

Grammar exercises on Relative clauses.

http://www.ego4u.com/en/cram-up/grammar/relative-clauses#exercises

Put the verb in brackets in the right tense

http://www.englisch-hilfen.de/en/exercises/if_clauses/type_1_statements.htm

http://www.englisch-hilfen.de/en/exercises/if_clauses/type_2_statements.htm

http://www.englisch-hilfen.de/en/exercises/if_clauses/type_3_statements.htm

http://www.englisch-hilfen.de/en/exercises/if_clauses/mix.htm

http://www.englisch-hilfen.de/en/exercises/if_clauses/mix.htm

http://www.englisch-hilfen.de/en/exercises/if_clauses/mix3.htm

Give the alternative structure

Although/In spite of conversions

Fill-in the blanks with the right option.

Exercises with FOR and SINCE