chris_____ (fall) off the ladder while he _______ (paint) the celling falling / painting was falling / was painting were falling / were painting. you ____ (study) when I _____ (call) you last night? were studying / called was studying / call studying / called. they ______ (drive) very fast when the policeman _____ (stop) them were driving / were stopped was driving / was stopped were driving / stopped. while i ________ (drive) to work yesterday, I ________ (see) an accident were driving / sew was driving / saw driving / saw. I ______ (read) a great book last week read reading. my friends _______ (drop in) for a visit while I _______ (watch) TV last night were dropping / was watching was dropping / was watching was dropping / were watching. when sue _____ (arrive) at the theater, her friends ____ (wait) or her inside arrived / were waited arrived / waited. i was watching FMS while my brother was working parallel actions interrumpted actions. it's a great movie. I have _____ that movie many times seen saw see. have you ____ really strange or interesting food? ate never eaten ever eaten. i'm sorry, but I _____ finished my homework yet have hasn't haven't. Eva, Thomas and Robert ____ hong kong many times have been to been to have been. have you finished answering all the questions...? yet ever never. she has a car, so she _____ there many times have drive has driven has drove. used for situations that are 100% real conditional zero 1st conditional. andy _____ (wash) the family car wash washes washed. mr. smith ____ (write) e-mails writes write. she____ (fix) my computer fixed fixes. the girls ___ (do) the shopping do does. used for possibilities in the future "will" 1st conditional conditional zero. if the sum ____ (rise) high, it _____ (become) very hot rises / becomes rises/ become. Unless you ___ (call) your mother called calls call. tha ___ (prefer) ________ (watch) drama movies ___ _______ (watch) action movies prefers / watching / to / watching prefer / watch .