3．Nanjing is a beautiful city． It won “China Human Habitat Environment Prize” _______ 2008．

A．at                 B．on                C．in                  D．by

2．--Do you know Nell Armstrong?

--Yes．He is the first man ________ on the moon．

A．walk            B．walks               C．to walk             D．walked

1．Sandy often takes her dog for ________ walk around the lake after supper．

A．a                   B．an                   C．the                D．不填