He wouldn't come ─ he said he was too busy.
他不愿来，他说他太忙。
The line is busy ─ I'll try again later.
占线——我过会儿再打。
I'll be too busy to come to the meeting.
我会很忙，不能到会。
Should anyone call, please tell them I'm busy.
如果有人打电话来，请告诉他我正忙着。
Try to get some rest ─ you have a busy day tomorrow.
休息一下吧——你明天还要忙一天呢。