He shows complete mastery of his chosen subject.

他精通自己选择那门科目。

Many of the subjects a prospective hotelman studies are in the field of business administration.

有志于当旅馆经理所学科目多属于业务管理范围。

Three subjects must be taken, viz., English, mathematice and history.

三个科目是必修, 英文, 数学和历史。

An encyclopedia covers many subjects.

百科全书内容涉及许多科目。

Detail! For inspection—port arms!.

科目！——持枪！。