theory
柯林斯词典
1. N-VAR A theory is a formal idea or set of ideas that is intended to explain something. 理论
Marx produced a new theory about historical change based upon conflict between competing groups. 马克思提出了一个新理论，认为历史变革是由于对立集团的冲突而产生的。
2. N-COUNT If you have a theory about something, you have your own opinion about it which you cannot prove but which you think is true. 观点
There was a theory that he wanted to marry her. 有种观点认为他想娶她。
3. N-UNCOUNT The theory of a practical subject or skill is the set of rules and principles that form the basis of it. 基础理论
He taught us music theory. 他教我们乐理。
4. PHRASE You use in theory to say that although something is supposed to be true or to happen in the way stated, it may not in fact be true or happen in that way. 从理论上说
Achieving these goals is relatively easy in theory, yet quite difficult in practice. 实现这些目标从理论上说比较容易，但在实践上却相当困难。
返回 theory
theory /ˈθɪərɪ/ (theories)
剑桥词典
- a formal statement of the rules on which a subject of study is based or of ideas that are suggested to explain a fact or event or, more generally , an opinion or explanation
- It was Ptolemy who propounded the theory that the earth was at the centre of the universe .
- This new evidence lends support to the theory that she was murdered .
- This research seems to give some validity to the theory that the drug might cause cancer .
- In Jungian theory, there are certain archetypes of human personality .
- In theory, women can still have children at the age of 50. 返回 theory
理论；学说；意见
economic theory 经济理论
scientific theory 科学理论
Darwin's theory of evolution 达尔文的进化论
He has a theory that the hole was caused by a meteorite . 他认为那个洞是陨石坠落形成的。
in theory
If something is possible in theory, it should be possible , but often it does not happen in that way.
理论上，从理论上讲
In theory, the journey should take three hours , but in practice it usually takes four because of roadworks . 按理说行程应该只要3小时，但由于道路施工，实际上通常会需要4小时。
例句