In fact, I'm not sure he even knows how to spell Aids.

事实上，我都不能确定他会不会拼艾滋这个单词。

youdao

I'm not sure he has lost pace. I still think he has that but what you lose with age is the capacity to repeat the pace.

我不确定他的速度是否不如以前快了，但我仍然相信他还是那么快，只是年龄大了持续快速的能力下降了。

youdao

I'm not sure he has lost pace. I still think he has that but what you lose with age is the capacity to repeat the pace. But over one short burst I'm sure he is still very quick.

我不确定他的速度是否不如以前快了，但我仍然相信他还是那么快，只是年龄大了持续快速的能力下降了。

youdao

And, I'm sure he's not worried about it at all.

而且，我肯，定他一点也不担心。

麻省理工公开课 - 固态化学导论课程节选

His friend told me that he doesn't have a girlfriend, but I'm not sure.

他的朋友跟我说他没有女朋友。可我还是不清楚。

I want to 实战 - SpeakingMax英语口语达人

I'm not sure if he still lives in San Francisco.

我不确定他是不是依然住在旧金山。

罗宾·威廉姆斯的家 - SpeakingMax英语口语达人

But I'm not sure he understands the securities laws or the legal definition of fraud.

WSJ: COMMON SENSE: Buffett May Know More About Derivatives Than Securities Law

"I'm not sure he can make up that kind of ground between now and Tuesday, " Adair said.

CNN: Giuliani fights political fall in Florida

"I'm not sure he knew how far he had fallen in the eyes of the people of Portland, " says Ganis.

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