idea
idea — noun
1. A thought about what someone could do, often forming a rough plan to deal with a
A thought about what someone could do, often forming a rough plan to deal with a situation or solve a problem.
Esteban came up with the idea of setting up a shared calendar for all the project deadlines.
idea + of + gerund phrase
It was Noa's idea to start a small book club at the local library.
it was [possessor] idea + to-infinitive
Darius had a clever idea for reducing waste in the company cafeteria.
The committee rejected Min's idea because it would cost too much money.
Vivek asked the group what they thought of his idea about hosting a weekend workshop.
- suggestion
more neutral; an idea put forward for others to consider
- plan
more detailed and concrete than an idea
- notion
more vague or informal; a half-formed idea
文法句型
idea + to-infinitive
idea + of + gerund/noun
idea + for + noun phrase
用法筆記
Common in conversational phrases such as 'That's a good idea!' or 'What a great idea!' to react to a suggestion.
常見錯誤
2. A general mental picture or degree of understanding about what something is like
A general mental picture or degree of understanding about what something is like, how it works, or what it involves.
The brochure gave Aoi a clear idea of what the national park had to offer.
give + idea + of + wh-clause
Ada had only a rough idea of how much the renovation would cost.
have + a rough idea of
Ravindra's demonstration helped the team form a better idea of how the new software worked.
The map gave Defne no idea of how steep the hiking trail actually was.
- notion
more informal and often vaguer than 'idea'
- concept
more abstract and formal; a general theoretical understanding
- impression
a partly formed or initial understanding, not necessarily accurate
- ignorance
complete lack of knowledge or understanding
文法句型
have an idea of + noun phrase
give someone an idea of + wh-clause/noun
have a clear/rough/vague idea
用法筆記
This sense is about having SOME understanding. When used in negative phrases like 'have no idea', the meaning shifts to a separate idiomatic sense (see sense 3). 'Have a good idea of...' suggests solid, useful understanding.
常見錯誤
3. Used in the fixed phrase 'have no idea' to emphasize that someone does not know,
Used in the fixed phrase 'have no idea' to emphasize that someone does not know, understand, or remember something, or to show that something is hard to imagine.
Christopher asked where the meeting was, but his assistant had no idea.
have no idea (standalone)
Tuan had no idea that the bakery closed early on Sundays.
have no idea + that-clause
Imani had no idea what to expect on her first day at the new school.
You have no idea how relieved Felipe felt when the package finally arrived.
- be clueless
informal; suggests complete ignorance
- not have a clue
informal, same meaning as 'have no idea'
- know
to have knowledge or information about something
文法句型
have no idea
have no idea + wh-clause
you have no idea + (how/what/that-clause)
用法筆記
The phrase 'I have no idea' is much stronger than 'I don't know' — it suggests complete lack of knowledge. 'You have no idea' is a fixed conversational opener used to emphasize that the listener cannot fully imagine a situation.
常見錯誤
4. A personal view or belief about what is true, right, or worth doing, shaped by a
A personal view or belief about what is true, right, or worth doing, shaped by a person's own thinking rather than by proven facts.
Élise has very strong ideas about how children should be encouraged to read.
have + strong ideas + about + wh-clause
Amani and Wei hold completely different ideas on what makes a good leader.
hold + ideas + on + topic
Many people reject the idea that material wealth alone leads to happiness.
Antonia's ideas about success have changed a lot since she started working at the non-profit.
文法句型
have + ideas + about + topic
the idea that + clause
ideas + on + topic
用法筆記
Distinguish from sense 1 (SUGGESTION): a belief is held personally and can exist without being shared, while a suggestion is offered to others as a possible course of action. 'Political ideas' and 'religious ideas' belong to this sense.
常見錯誤
5. The central purpose, intention, or reason that explains why a particular action,
The central purpose, intention, or reason that explains why a particular action, plan, or system exists.
The whole idea of the training course is to prepare new staff for their roles.
the whole idea of + noun + is to + verb
The idea behind the festival is to bring the community together through food and music.
the idea behind + noun phrase + is to + verb
Pim explained that the main idea of the new policy was to reduce waste in the factory.
The original idea of the simple design was to make the website easy for elderly users.
文法句型
the idea of + noun + is to + verb
the idea behind + noun phrase
the main / whole idea
用法筆記
This sense almost always appears with 'the' not 'a/an' — 'the idea' — and is commonly followed by 'of + noun + is to' or 'behind + noun'. The phrase 'the idea is to...' is a very common conversational pattern.