they always sell their pants--a very high price.1 sell 2 sale 3sells 4selling
问题描述：
they always sell their pants--a very high price.1 sell 2 sale 3sells 4selling
答
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答
不是很清楚楼主的题干需要填空的是哪 如果是a前面 填selling 动词ING作伴随状语