— Did he notice you enter the room?— I don’t think so. He _____ to the radio with his eyes shut.
If it was not an accident, he must have done it _____ .
Many students signed up for the ____ race in the sports meeting to be held next week.
____ Knowledge of English is a must in international trade.
Cloning the sheep ----Dolly is a big ____ in science.
----Who did you spend last weekend with? ---- _________________ .