PLEASE REVIEW ALL CONDITIONALS:
http://www.grammar-quizzes.com/conditionsum.html
THEN
PRACTICE: DO ALL OF THEM!!!
1.http://www.englishclub.com/grammar/verbs-conditional_quiz.htm
2.http://grammar.ccc.commnet.edu/grammar/quizzes/conditional_quiz.htm
3.http://www.usingenglish.com/quizzes/36.html
4.http://www.testyourenglish.net/english-online/grammarquiz/ifsquiz.html