my blue trousers---worn out.one pair of trousers---not enough
问题描述：
my blue trousers---worn out.one pair of trousers---not enough
A IS are B are is C is is D are is
答
B为什麽不用单数？当眼镜， 裤子， 袜子， 鞋 等做主语时， 谓语一般用复数。但当前面用 a pair of 修饰时， 谓语在数上和pair 一致， 即用单数