7. Was, were

https://sites.google.com/site/easygrammar4kids/simple-past/To-Be-past

https://www.funbrain.com/cgi-bin/verb.cgi?A1=s&A2=0&A3=1

http://www.carmenlu.com/first/grammar/pastbe1_5.htm

http://www.grammar.cl/english-games/was-were-short-answers.htm

http://www.carmenlu.com/first/grammar/pastbe1_4c.htm