We should always keep ______well-informed of the changing information.

Smith and his girlfriend went to Chenyi Square to celebrate the New Year, never _________.

This is the factory ____ we worked a yearago

His writing is so confusing that it’s difficult to make out ________ it is he is trying to express.(2011·安徽，33)

call me at 9:00 o’clock tomorrow morning ,when Ia lecture atHarvard