I.单选。选一个最佳答案。（每小题1分，共20分）
( )1. Tom was born __________ September 13, 1982.
A. at B. in C. on D. from
( )2. The old man _____________ after he went to see the doctor.
A. started hiccupping B. started to hiccup
C. stopped hiccupping D. stopped to hiccup
( )3. -- __________ did Mr. Smith stay in Beijing?
-- For about two weeks.
A. When B. How C. How long D. How often
