Here are some webpages that have explanations and quizzes/exercises about relative clauses (which are also called adjective clauses):
The quiz for these is at the bottom of this webpage.
(Essential & non-essential = restrictive & non-restrictive)
And the first three links here are perfect:
Here is a whole page on combining sentences:
Direct and indirect speech:
There are many good webpages among those search results. Check 'em all out!
Infinitive and gerund phrases are dealt with here:
And there's a good quiz at the bottom of the page.
I'm not sure what you mean for #2 in your question. Go through these sites, and see what you find:
Use only the free stuff here!
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