—Tom, how forgetful you are! I found you left your key in the keyhole this morning. —Oh, dear! _______.
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.
____ it will do us harm or good remains to be seen.