I'd never seen him like this, so sure of himself, so in command.

我从未见过他像这样，如此自信，如此得心应手。

《柯林斯英汉双解大词典》

The drunk seemed quite sure of himself.

醉汉像是很有把握似的。

youdao

I had never met anyone so sure of himself.

我还从未见过一个人如此自信过。

youdao

So, he started asking himself the question, "What can I be sure of?"

他首先问自己一个问题,"我究竟能够确信什么呢"

耶鲁公开课 - 心理学导论课程节选

Yet Hoover was sure of himself and continued to apply useless remedies.

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Then again, neither has Matt and he seems pretty sure of himself.

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But this is a guy so sure of himself that he walked away from a million-dollar payday when he was barely out of high school, who turned down a billion-dollar offer for Facebook from Yahoo!

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