theory
theory — 名詞
1. a set of well-tested ideas that explains why something happens in nature or soci
理論
經科學驗證的系統化概念
a set of well-tested ideas that explains why something happens in nature or society, based on evidence and careful study
Darwin's theory of evolution explains how species gradually adapt to changing environments.
達爾文的演化理論解釋了物種如何逐漸適應環境的變化。
collocation: theory of [something]
Noa tested the theory by measuring water temperature at different depths.
Noa 透過測量不同水深的溫度來驗證這項理論。
transitive use: test a theory
Élise wrote her thesis on a theory about how children learn their first language.
Élise 的論文主題是一個關於幼兒如何學習母語的理論。
According to the Big Bang theory, the universe began with an enormous explosion.
根據宇宙大爆炸理論，宇宙始於一場巨大的爆炸。
Takeshi's experiment supported the theory that sleep helps strengthen new memories.
Takeshi 的實驗結果支持了睡眠有助於鞏固新記憶的理論。
- hypothesis
a proposed but not yet fully tested explanation — narrower and more tentative than a theory
- model
a simplified representation used to analyse or predict a system — often more concrete and specific
- framework
a basic structure of ideas that supports further thinking — broader and less formal than a scientific theory
- doctrine
a set of beliefs held and taught by a group — often implies authority or ideology rather than empirical testing
文法句型
theory of [something]
theory that [clause]
[verb] + theory
用法筆記
Commonly constructed with 'of' ('theory of relativity') or a 'that'-clause ('the theory that...'). In everyday English, 'theory' is sometimes used loosely to mean 'an untested guess,' but in academic and scientific contexts it refers to a well-supported explanatory framework supported by evidence.
常見錯誤
2. applies when something should be possible according to an idea or system, but in
理論上
按照推論與現實情況可能不同
applies when something should be possible according to an idea or system, but in reality it often works out differently
In theory, the faster computer should finish the task in half the time.
理論上，速度更快的電腦應該能用一半的時間完成任務。
adverbial phrase: 'in theory' at start of sentence
The new policy makes sense in theory, but it is hard to put into practice.
這項新政策理論上說得通，但在實務上很難落實。
contrast pattern: 'in theory, but...'
Roya knew that in theory all the data was safe, yet she still made backups.
Roya 知道理論上所有資料都是安全的，但她還是做了備份。
In theory, raising taxes should reduce pollution, but some experts disagree.
理論上，提高稅收應該能減少污染，但有些專家不同意。
Rafael agreed with the idea in theory, though he worried about the cost.
Rafael 理論上同意這個想法，但他擔心費用的問題。
- in principle
similar meaning but slightly more formal, focusing on the underlying concept rather than a hypothetical scenario
- theoretically
adverb form that can replace the phrase 'in theory' in most contexts
- in practice
the most direct contrast — what actually happens versus what is supposed to happen
- in reality
similar to 'in practice', emphasizing the real-world outcome rather than the expected one
文法句型
in theory
in theory ... but in practice / in reality
用法筆記
The phrase 'in theory' is the most common form of this sense; the adverb 'theoretically' can be used in the same way ('Theoretically, the machine should work'). The contrast pattern 'in theory...but in practice/reality...' is especially frequent in discussions of plans, policies, and proposals.