Sheldon Cooper: Dad, do you believe that fossils are millions of years old?
George Cooper Sr.: I guess. Why?
Sheldon Cooper: Well, Mom believes the world was only created 6,000 years ago.
George Cooper Sr.: Yeah. So?
Sheldon Cooper: Are these differences a sticking point in your marriage?
George Cooper Sr.: Not at all.
Sheldon Cooper: Why?
George Cooper Sr.: Simple. We never talk about it.
Sheldon Cooper: So you just avoid discussing topics you don't agree on?
George Cooper Sr.: At all costs.
Sheldon Cooper: Hearing that further convinces me I'll never get married.
George Cooper Sr.: Never say never.
Sheldon Cooper: Why not? You just said it twice.
以上對話中出現了口語中很常見的一個回答「I guess.」。相信大家都知道，guess 本身是表示「猜」的意思。那麼 I guess 是表示「我猜」嗎？
我們以前在英語課本中最常見到的表達是這樣的：
I guess he got stuck in traffic.
Guess what I did for the whole of the first week.
這兩個句子確實有「猜」的意思。
第一個句子中的 I guess 在字典中的釋義是：If you guess something, you give an answer or provide an opinion which may not be true because you do not have definite knowledge about the matter concerned.
此時， I guess = I suppose = I believe，表示「我猜測」、「我認為」或「我覺得」。
示例：
Yvonne guessed that he was a very successful publisher or a banker. 伊馮娜猜測他是一位非常成功的出版商或銀行家。
I guess I can manage alone. 我想我一個人可以應付。
I guess he was wrong. 我想他錯了。
第二個句子 guess 則用於句子開頭，後面直接加賓語。通常用於引出令人驚奇或激動的事，「你猜……！」
示例：
回到開頭的對話中（「I guess.」），我們可發現 guess 後面其實並沒有內容。如果套進上面2種句式中，這個句子是不完整的。
其實，I guess 在字典中還有一個釋義：
Often used as an affirmative answer when one is not completely certain or does not want to fully commit. 「我想是吧。」 此時，I guess 確實可以單獨使用。
示例：
Bob: "You look a little down today. Everything alright?"
Mary: "I guess. I've just been feeling vaguely melancholy lately."
A: "It's supposed to be sunny today, right?"
B: "I guess. I haven't checked the weather."
其實，根據意思來看，I guess 單獨使用的時候也可認為是省略了賓語 so 罷了。其實，I guess so 也是很常見的回答。
I guess (so). = I believe so.; I expect (so).; I suppose (so).; I suspect (so).; I think so.
示例：
'Are you ready to go?' 'Yeah, I guess so.'「你準備好出發了嗎？」 「是的，我想可以了。」
'I think you're being paranoid.' 'Yeah. I guess so.' 「我認為你是多疑了。」 「是的，我想是的。」
'Were you happy with the result?' 'Well, I guess so.'
'Does that answer your question?' 'Yeah, I guess so.'
跟 I guess so 相反的回答是 I guess not。看清楚了，是 not，不是 no。
而且，表示否定的時候，I guess 後面不能省略 not。
I guess not. = I don't think so.; I expect not.; I suppose not.; I suspect not.; I think not.
示例：
'They aren't coming, then?' 'I guess not.' 「這麼說，他們不來了？」「我想是吧。」
'Is Tom coming?' 'I guess not—it's getting pretty late.'
'So you won't be going there again?' 'I guess not.'
'It's almost too late to go to the movie. Shall we try anyway?' 'I guess not.'
'So no one actually saw him arriving?' 'No, I guess not.'