1
be required for sth
A valid ID is required for entry.
进入需要有效身份证件。
必需的；必要的
先理解核心含义，再看它在真实句子里的用法。
必需的；必要的
Necessary; obligatory; mandatory.
A valid ID is required for entry.
进入需要有效身份证件。
必需的；义务的；强制性的。
Necessary; obligatory; mandatory.
Reading the safety manual is required before using the equipment.
使用设备前必须阅读安全手册。
Please bring all required documents to the interview.
请携带所有必需的文件参加面试。
A valid passport is required for international travel.
国际旅行需要有效护照。
A valid ID is required for entry.
进入需要有效身份证件。
All passengers are required to fasten their seatbelts.
所有乘客都必须系好安全带。
This course is required by the curriculum.
本课程是课程大纲所必需的。
Silence is required of all students.
所有学生都需要保持安静。
Not this
The documents require.
Use this
The documents are required.
“require”是动词，不能直接作表语；应用形容词“required”，前面加系动词“are”。
Not this
This course is required of graduation.
Use this
This course is required for graduation.
表示“为…所必需”时，应为“required for”，而不是“required of”，后者通常用于人。
Focus on the distinctions below. Other candidates are kept compact until a reliable usage note is available.
必修课
This is a required course for all first-year students.
这是所有大一学生的必修课。
必读材料
The professor assigned three books as required reading.
教授指定了三本书作为必读材料。
必填字段
All required fields must be filled in before submitting the form.
提交表格前必须填写所有必填字段。
必备技能
Communication and teamwork are required skills for this job.
沟通和团队合作是这份工作的必备技能。
必需文件
Please bring all required documents to the interview.
请将所有必需文件带到面试现场。
所需水平
Applicants must have a required level of English proficiency.
申请者必须具备所需的英语水平。
必读读物
This book is required reading for all students.
这本书是所有学生的必读读物。
必修课程
Calculus is a required course for engineering majors.
微积分是工程专业的必修课程。
根据需要
The medication should be taken as required for pain relief.
根据需要服用药物以缓解疼痛。
Use required naturally, then get feedback on meaning, tone, grammar, and phrasing.
Revisit a common error or keep this word in your review list.
想象‘re’（再次）加‘quired’（要求），一再要求的东西就是‘必需的’。
作为形容词，'required' 的使用场合较为广泛，既可用于正式场合（如官方文件、规则说明），也可用于日常交流（如日常任务、必需品）。但比较常见于需明确指示必要性的语境，如表格填写、课程要求、工作流程等。整体语气中性，不带有特别正式或随意的情感色彩。
常与 for, to 或 that 从句连用，表示必要或强制。
Dictionary facts from ECDICT, WIKTIONARY, WORDNET.