My dear students,
I thought you may want some more structured practice on conditional sentences, so here goes this German website. It’s called English Grammar Online For You, or simply EGO4U. It’s got such a collection of exercises that it looks impossible to finish it up.
I suggest you have a go at some of the exercises on this page. Don’t be put off by the fact that it is a German website. Everything is in English.
If you find they are too difficult, please tell me. Oh, by the way, these are the type of exercises I usually look for when I prepare my exams. Actually, most of the activities are directly copied-and-pasted from some web site or other. Isn’t that a good piece of advice?