—____________ you_________ the editor at the airport? —No, he__________ away before my arrival.
To enjoy the scenery,Irene would rather spend long hours on the train _______ travel by air.
The pianist waited for silence a while _______ he began to play the violin.
Scientists say it may be five or six years _______ it is possible to test this medicine on human patients.
It was some time _______ we realized the truth.
Roses need special care _______ they can live through winter.