Употребите предложения в Present Perfect или Past Simple 1. Students are cleaning their classrooms. (already, last Saturday 2. The teacher is explaining a new rule. (Just; at the previous lesson) 3. Ann is doing her homework now. (just; on Friday) 4. They are discussing this problem again. (many times; a few days ago) 5. Granny is making a birthday cake. (just, yesterday)