I can think of many cases ______students obviously know a lot of English words and expressions but couldn’t write a good essay .
The two countries were ______ between 1989 and 1992.
The oil must be used up, ____ the light went out.
I like traveling by sea____ it is not rough.
---Has the train arrived? ---No, it all will be late ___ half an hour.
I wanted two seats____ Madame Gurie for Friday night, so I rang the cinema to seeif I could book two tickets.