difficult to understand, the lecture was poorly thought of.

When he came back, he found the bag he had ______________ over the seat was gone.

Recently a survey _______ prices of the same goods in two different supermarkets has caused heated debate among citizens.

---Where has Mary been? I haven't seen her all day?---Oh,in order not to be disturbed, she spent the whole day __in the study, ___ her report.

The disco music，digitally________in the studio，sounded fantastic at the party that night.