auxiliary verbs

question tags:

https://www.englishclub.com/grammar/verbs-questions-tag_quiz.htm

http://www.better-english.com/grammar/questiontags.htm

http://www.englishgrammarsecrets.com/questionstags/exercise3.swf

http://www.englishgrammarsecrets.com/questionstags/exercise4.swf

http://www.englishgrammarsecrets.com/questionstags/exercise6.swf

https://www.usingenglish.com/quizzes/233.html

echo questions:

http://www.ecsscotland.co.uk/news/english-grammar-help-echo-questions/

https://docs.google.com/viewer?a=v&pid=sites&srcid=ZGVmYXVsdGRvbWFpbnxhbGV4YW5kcmFic2Nob29sfGd4OjI2ZmYzM2M0MDhhN2FmOTc

agreeing/disagreeing (so/neither)

http://www.tolearnenglish.com/exercises/exercise-english-2/exercise-english-49198.php

http://www.englishexercises.org/makeagame/viewgame.asp?id=6187