问题补充:
good advice! It’s so helpful to us.
A. How
B. How a
C. What
D. What a
答案:
A. How
B. How a
(答案→)C. What
D. What a
解析:How,How a,What What a之间的区别
How +形容词+ a +名词+ 陈述语序
How+形容词或副词+ 陈述语序
What +名词+陈述语序
What+a+形容词+名词+ 陈述语序
What+ 形容词+复数名词+ 陈述语序
What+ 形容词+不可数名词+ 陈述语序
根据题意,good advice中心词为advice,是不可数名词,故选D.