compulsory/kəm'pʌlsərɪ/

a. if sth is compulsory, it must be done because of a law or rule

a. 必须做的，义务的；强制的：English is a compulsory subject. 英语是一门必修科目。

◇compulsory education 义务教育

构词com- + puls（= push推）+ -ory

音组-ory/-ərɪ/

compulsory; factory; history; victory