She suffers from a lack of confidence.

　　她深受缺乏自信心之苦。

　　He suffers from a lack of self-regard.

　　他缺乏自尊。

　　His ideas lack depth.

　　他的想法缺乏深度。

　　They were exhausted from lack of sleep.

　　他們因睡眠不足而疲憊不堪了。

　　Anxiety can be caused by lack of sleep.

　　睡眠不足可能導致焦慮。

　　Her lack of experience told against her.

　　她缺乏經驗對她不利。

　　Her brain was befogged by lack of sleep.

　　她因缺乏睡眠而頭腦昏沉。