–I am so sorry to have come late for the meeting.-It’s not your fault. With rush-hour traffic and heavy rain, it is no wonder you were late.
We _____ on this project for four hours. Let’s have a rest.
Experiments of the kind ____ in both the U.S. and Europe well before the Second World Wall.
By the time Jane gets home, her aunt ____ for London to attend a meeting.
His sister left home in 1998, and ______ since.
The water ____ cool when I jumped into the pool for morning exercise.