Here are some exercises about the conditional clauses

http://www.ego4u.com/en/cram-up/grammar/conditional-sentences/type-1/exercises
http://www.ego4u.com/en/cram-up/grammar/conditional-sentences/type-1/exercises?02
http://www.ego4u.com/en/cram-up/tests/conditional-sentences-2
http://www.ego4u.com/en/cram-up/grammar/conditional-sentences/exercises
http://www.ego4u.com/en/cram-up/grammar/conditional-sentences/exercises?02
http://www.ego4u.com/en/cram-up/grammar/conditional-sentences/type-2/exercises
http://www.ego4u.com/en/cram-up/grammar/conditional-sentences/type-2/exercises?02