oat is smarter than mine, but mine is _________ cheaper thanyours.

Could my English be as good as yours , Judy——I think you should practice it as _____as you can.

Looking for information on line today is very easy ; the _____________is how to tell whether the information you are getting is useful or not.

Having ________ exercise every day will do greatgood to your health.

下列各句中不含通假字的一项是（ ）