Many people have been ill from a strange disese these days,_____we have never heard of before.

题目

Many people have been ill from a strange disese these days,_____we have never heard of before.
A.one
B.that
C.it
D.this
讲一下其他三个不能选的理由!讲不清原因的别进来!

答案

B. that 没有接在逗号后面的习惯.
C和D明显不行.因为构成的的从句不通顺.