.I had been puzzled over the problem for over an hour without any result, _____ all at once thesolution flashed across my mind.
They dug ,then put the box in it.
Either the boy or his sister must have dinner here.
I tried every to make him give up smoking.
Being poor, she had to borrow a new so as to attend the party.
If it was not an accident, he must have done it .