单项选择题
A．increases the ability to think B．is the best time for thinking C．is better for thinking than is very warm weather D．decreases the ability to think
A．a great effect on everyone's intelligence B．same effect on most persons' intelligence C．some effect on a few persons' intelligence D．no effect on most persons' intelligence
A．I always have difficulty choosing birthday presents. B．Once I gave Tom a bottle of champagne as a birthday present. C．The present I gave Tom was a great surprise to him. D．To my surprise, something funny happened in Tom's birthday party.