My brother entered the room and sat in the sofa, ________.
The young man went into the cinema and after ____ seemed half an hour he came out.
It was quite a serious mistake, ____caused by carelessness.
____ method you choose, so long as you finish the job on time.
I am so glad that I have found the same modern computer ____ I am working on.
We should do more such exercises in the future, I think, ____ we did yesterday.