Правильно выбрать форму глагола: 1.the 's time to finish your studies a-strikes b-has stricken c-is striking 2. the problem now. a-understand b-are understanding c-have understood 3. today, but i saw him yesterday a-didn't see b-don't see c-haven't seen 4. work before they came. a-had done b-has done c-did 5.when telephone rang. a-are talking b-were talking c-have a talk