单项选择Asaprofessionalbasketballplayer，heisserious

问题详情：

单项选择

As a professional basketball player，he is serious ________ playing basketball.

A．about             B．at 

C．of                D．to

【回答】

A　点拨：be serious about doing sth.为习惯表达，意为“对做某事是认真的”。

知识点：介词和介词短语

题型：选择题