问题

tists have advanced many theories about why human beings cry tears , none of ______ has been proved.

A:whom
B:which
C:what
D:that;

正确答案是：

同类题型

In South Korea, most students get to school ________.

My friends and I often _________ afterschool.

mind, she is the most wonderfulteacher that I’ve ever known, _________ is able to get across to her students________ she really thinks and means.

You are late again, Tom?—Sorry, but I got________a heavy traffic jam.

testing this method on patients, DrBaker had tests for two yearson three hundred dogs