Practice grammar

This two topics are difficult to me and those links it is a perfect level to improve and understand perfectly the grammar:

Conditionals:

Have to and don't have to (use)

This exercises help me to understand have to use in different situations and with some examples to do more easily understand.

http://www.eclecticenglish.com/grammar/HaveTo1A.html

Future forms:

This quiz is perfect to practice future forms and all its forms completing sentences.

http://esl.about.com/library/quiz/blgrquiz_future.htm