- Why are you so popular with your students?- As a teacher, I seldom give my stu
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— Why are you so popular with your students?
— As a teacher, I seldom give my students so difficult a problem ____ they cannot work out
A.as
B.that
C.if
D.which
试题答案
A
考查定语从句。先行词为a problem，后面的从句they cannot work out后缺少宾语，所以使用关系代词，so… as，为固定搭配，所以选A。