1 my friend was talking to Professor ivanov when I saw him
2 when the students heard the bell, they were getting and leaving
3 the two men were discussing something when we interrupted them
4 the girl was falling and hurting herself while she rode her bicycle
5 we were just leaving the house when the telephone rang
6 he was sitting in a cafe when i saw him
7 when i went out the sun is shining
8 while she was playing the piano i was writting a letter
9 when the telephone rang we were having dinner
10 she was going to the plant when i met her