Tom has to wear a uniform today.(就划线部分提问)划线部分是a uniform

问题描述:

Tom has to wear a uniform today.(就划线部分提问)划线部分是a uniform

a uniform 是物,并且没有涉及需要选择的问题,所以不用which,用what 提问.
答案是 What does Tom have to wear today?