. It is only when we cannot see clearly we come to see important our eyes are.A. that; w

问题补充：

. It is only when we cannot see clearly we come to see important our eyes are.

A. that; what

B. which; what

C. that; how

D. which; how

答案：

A. that; what

B. which; what

(答案→)C. that; how

D. which; how

解析：第一空考查强调句型it is +被强调部分 + that…。第二空考查感叹句，对形容词感叹用how。句意：只有到我们失明时我们才知道眼睛有多重要。