valid
valid — adjective
1. Something that is valid is based on facts, good reasons, or clear logic, so it c
Something that is valid is based on facts, good reasons, or clear logic, so it can be seriously considered or trusted.
Xiu made several valid points during the team meeting about the new project.
valid + point (common noun collocation)
The teacher explained why his argument was not valid in the science report.
not valid (negation pattern)
Padma raised a valid concern about the budget, so the manager agreed to review it.
Is there a valid reason for arriving at work two hours late?
Christopher could not find a single valid excuse for missing the exam.
- sound
stronger than valid — implies the argument has both correct logic and true facts
- reasonable
focuses on fairness and common sense rather than formal logic
- legitimate
suggests acceptance within a social, legal, or moral system
- invalid
the direct opposite; not based on truth or reason
- unreasonable
not based on good sense or fair thinking
文法句型
valid + noun
not + valid
用法筆記
Commonly used with abstract nouns like point, argument, reason, excuse, concern, or question. Very frequent in negative structures — 'not valid' — when rejecting a claim or explanation.
常見錯誤
2. When a ticket, document, or official paper follows the rules of a system — usual
When a ticket, document, or official paper follows the rules of a system — usually within a set time limit — it is considered valid.
Sirin's passport is still valid for another six months of international travel.
still valid + for + duration
You cannot board the train with a ticket that is no longer valid.
no longer valid (expiry pattern)
The coupon is valid until the end of this month at any store in town.
Asher checked that his student ID was still valid before buying the discounted ticket.
文法句型
valid + for [time period]
valid + until [date]
still valid
no longer valid
用法筆記
Subject is typically a ticket, passport, visa, ID card, coupon, subscription, membership, or licence. Frequently followed by 'for' (duration), 'until' (expiry date), or 'in' (location).
常見錯誤
3. A legal document, agreement, or action is valid when the law recognizes it as ha
A legal document, agreement, or action is valid when the law recognizes it as having full authority and binding power.
The contract is valid only if both parties sign it in front of a witness.
valid + condition (only if)
Mauricio's will was declared valid by the judge after the court hearing.
passive: declared valid + by [authority]
A verbal agreement without written proof may not be legally valid in court.
The marriage certificate from the island is not valid under Taiwanese law.
- lawful
broader term meaning allowed by law; not limited to documents and agreements
- binding
emphasises that a contract or promise must be followed
- enforceable
can be made effective by a court if one party does not obey
- void
having no legal force from the beginning, as if it never existed
- null and void
legal phrase meaning completely without legal effect
文法句型
legally valid
declared valid
valid under [law]
valid + only if [condition]
用法筆記
Subject is typically contract, will, marriage, agreement, signature, or legislation. Frequently passive — 'declared valid,' 'ruled valid,' 'held to be valid.' Common in formal legal writing and court contexts.