1. Perhaps/maybe
These two words are used for saying that you are not certain about something, or that something may or may not be true.
這兩個詞可以用在你對某事不確定的情況下，或是表達某事可能是真的也可能是假的。
Perhaps is more formal and is used in writing while maybe is used more in spoken English
“perhaps”更加正式，常用在寫作中，而“maybe”更多用在口語中。
e.g. I wondered if perhaps he had changed his mind about attending the party.
例句：我在想關于參加派對這件事，他是不是改變主意了。
e.g. ‘When can you give me an answer?’ ‘I don’t know. Maybe tomorrow.’
例句：“你什么時候能給我答復?” “不知道，也許明天吧。”
2. Probably/possibly
These two words can confuse even native speakers. Probably is used for saying that something is likely to be true, and possibly that it may be true but you are not certain.
這兩個詞非常容易混淆。“Probably”用來表達某件事很可能是真的，“possibly”則表示這件事可能是真的，但你并不確定。
e.g. If house prices are low, it’s probably because there is a lack of demand.
例句：如果房價很低，那么很可能是因為需求少。
e.g. ‘Would you consider moving to another country for your work?’ ‘Possibly, I’m not sure.’
例句：“你會因為工作原因考慮移居其他國家嗎?”“可能吧，我不確定。”
3. Apparently
It is used when what you are saying is based on what you have heard, not on what you know is true and therefore fact.
當你聽說了某件事而不是你自己確定這件事是真的的時候，你可以用“apparently”來表示這件事是事實。
e.g. Apparently, she resigned because she had an argument with her boss.
例句：顯然，她辭職是因為和老板吵了一架。
e.g. There is, apparently, going to be an announcement about the new CEO tomorrow.
例句：顯然，明天就會有新總裁的通知了。
4. As far as I know/ as far as I am aware
These two expressions are used when you have partial (incomplete) knowledge of an issue or fact.
如果你對某個問題了解得不是很全面，就可以用這個詞。
e.g. No one has complained, as far as I know.
例句：就我所知，沒有人抱怨。
e.g. As far as I am aware, the invitations to the party have all been sent.
例句：就我所知，派對的邀請函已經全部發(fā)出了。
5. To the best of my knowledge
This phrase is used for saying that you think something is true, but you are not completely certain. This is quite a formal expression.
當你認為某事是真的，但又不確定的時候可以用這句話。
e.g. To the best of my knowledge, no similar book has been published.
例句：就我看來，還沒有類似的書出版過。
6. Not to my knowledge
This is used for saying that you think something is not true, although you are not completely certain.
當你認為某事不是真的，但又不確定的時候可以用這句話。
e.g. ‘Has the report been sent yet?’ ‘Not to my knowledge.’
例句：“報告交上去了嗎?” “我覺得沒有吧。”
7. I imagine/suppose/guess
These are used when you think something is probably true, but you can’t be sure. “Guess” is more frequently used in American English, although you can hear it in British English, too. “Suppose” is more characteristic of British English and is often used in the negative.
這些詞可以用在當你認為某事可能是真的，但又不確定的時候。“guess”更多地出現(xiàn)在美式英語中，盡管也有英國人會用。但是“suppose”是更加地道的英式英語，而且經常用在否定句中。
e.g. I imagine they’ve already left for the airport.
例句：我認為他們已經離開機場了。
e.g. I suppose she must be delighted about getting the job.
例句：我認為她得到這份工作一定很開心。
e.g. I don’t suppose you’d consider staying for another week?
例句：我不認為你會再待一個星期。
e.g. I guess he will want to meet all the team members before the conference.
例句：我猜他想在會議前和團隊成員見面。
