adj.強制的；勢在必行的；義務的

Attendance at evening prayers is not compulsory. 參加晚禱并非硬性規(guī)定。

I think it is compulsory. 我認為這是非做不可的。

The car insurance is compulsory. 這項汽車保險是強制性的。

I think it is compulsory to look over the house. 我認為檢查這棟房子勢在必行。

Building model stars is a compulsory task. 建立恒星模型是一項勢在必行的任務。

Is English a compulsory subject? 英語是必修科目嗎？

Is military service compulsory in your country? 你們國家實行義務兵役制嗎？