一．.单项选择（共20 小题；每小题1分，共20分）
( )1. The weather in March is like ______ baby’s face. It changes quickly.
A. the B. a C. an D. /
( )2.They never knew ______in one hundred years.
A. what the weather is like B. what the weather would be like
C. What the weather would be D. How the weather was
( )3. 一 The problem is too difficult. Can you show me _______ , Andy? 一 Sure.
A．what to work it out B．what to work it out
C．how to work it out D．how to work out it
