required
adj. 必需的
近义词：compulsory，essential，necessary，vital，forced，forcible，indispensable，mandatory，requisite，obligatory，prerequisite，needful，needed，elective，
英英释义
Adjective
- necessary for relief or supply;
"provided them with all things needful"
- required by rule;
"in most schools physical education is compulsory" "attendance is mandatory" "required reading"
例句
用作形容词(adj.)
- I did more work than required.我做了比所被要求的来得更多的工作。
- All passengers are required to show their tickets.所有乘客都必须出示车票。
- Learning to walk again after his accident required great patience.他出事后重新学习走路要有极大的毅力。
- The ships required the protection of naval and air power.船只本身需要海军和空军的保护。