Increasingly lacking confidence about myself, I am nervous of the coming exam.

我对自己越发没自信，因而对即将到来的考试也感到非常焦虑。

youdao

"You may be a qualified candidate, but none of that matters if you walk into that interview lacking confidence," he added. "Don't act too confident, though."

“你可能是一个称职的求职者，但如果面试时缺乏信心，再称职也无济于事，”他补充说道，“然而，不要太过分自信。”

youdao

She felt nervous, increasingly lacking in confidence about herself.

她感到紧张，对自己越来越缺乏信心。

《柯林斯英汉双解大词典》

The Youth Sport Trust said schools needed to do more to address issues such as girls feeling body conscious or lacking confidence in their abilities.

BBC: Health

But he said he became suspicious of Mr Wilkinson, who he described as "desperately disorganised" and "lacking confidence", and on one of his visits secretly took a photograph of him.

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Survivors are often too afraid or embarrassed to speak out on what they have been through, sometimes isolated from their communities and lacking confidence those who abused them will face justice.

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