n.马甲;背心;
例句:
That waistcoat won't meet.
那件背心腰小了,扣不上了.
The waistcoat should be very beautiful if it is made in army green.
用国防绿的布料做这件马甲应该很好看.
I always wear a waistcoat.
我经常穿着一件马甲.