compulsory
单词辨析：
普通用词，多指由客观因素决定的，是必不可少的。
Water is necessary for life.
水是生命不可或缺的。
It is necessary to perform an operation on him.
必须对他实施手术。
It is not necessary to wear a business suit.
不一定要穿商务套装。
If necessary, we can always change the date of our trip.
必要的话，我们随时可以改变旅行的日期。
指由法律、上级命令等规定或强制的。
compulsory circulation/education/insuranc
强制流通/义务教育/强制保险
Questions 1-6 are compulsory.
1至6题为必答题。
Is military service compulsory in your country?
你们国家实行义务兵役制吗？
Swimming is compulsory at their school.
在他们学校，游泳是必修课。
Many young men in that country tried to get away from compulsory military conscription.
那个国家的很多年轻人试图逃避强制征兵的政策。
相关例句：
English, Maths, ICT and science are compulsory subjects.
英语、数学、信息与通信技术和科学是必修科目。
Russian is the one compulsory foreign language on the school curriculum.
俄语在学校课程设置中是一门必修的外语课。
Some subjects, such as mathematice, physics and English, are compulsory for the students in this department.
有些课程，比如数学、物理和英语，本系学生都是必修的。
Britain did not introduce compulsory primary education until 1880
直到1880年，英国才开始实行初等义务教育。
And the balanced development of compulsory education is the premise and foundation.
而义务教育的均衡发展是这一理想实现的前提和基础。
Many young men are trying to get away from compulsory military conscription.
很多年轻人试图逃避强制征兵的政策。