Question

______ matters most in learning English is enough practice.

1. A.
   What
2. B.
   Why
3. C.
   Where
4. D.
   Which

Answer 1

A
思路分析：________matters most in learning English是is的主语从句，而在主语从句中谓语动词matters缺少主语，故选A项。what引导主语从句且在从句中充当主语。
【点评】本题考查名词性从句，难度中等。这类题要注意分析句子成分：先找出主句的谓语，再找从句谓语；先看从句中是否缺少主语和宾语，再考虑其他成分。