雨一直下了三天。 ________________ for three days.

单项选择题When the children were very young, ________.

单项选择题Acid rain ________.

单项选择题According to the ad，if you buy the book on April 28，2009， you just pay () for it.

A．＄17.50
B．＄35.00
C．＄52.50
D．＄50.00

单项选择题What did the headmaster tell the two teachers on the next day？

单项选择题A．policemanB．motherC． father D．brother