. Jack is always occupied __________ his work, which makes him have no time to stay with his family.
There are five pairs, but I'm at a loss which _____ to buy.
He was not an actor, who often appeared on stage, _____ a writer, writing stories.
Please make my excuse at tomorrow's meeting. I've got too much work _____.
I don't know whether to stay in teaching or _____ another job.
He transplanted the little tree to the garden _____ it was the best time for it.