bite off more than sb.can chew貪多嚼不爛吃東西的時候如果吃太多，嘴巴塞滿嚼不動，最後還是得吐出來一些。所以這個習語用來形容「接太多工作或做太多事，多到自己無法承受」。要注意bite off有「咬掉，咬下來」的意思，bite只是咬。
看看老外聊天時怎麼用bite off more than sb.can chew：
Allen: Have you seen Grace this morning?
Amy: Actually, she called in sick today. Allen: It's not because of her part-time jobs, is it?
Amy: I'm afraid so. She bites off more than she can chew.
Allen: I can't blame her. She's in financial difficulty now.
艾倫：你今天早上看到格雷絲了嗎？
埃米：其實呢，她今天請病假。艾倫：該不會是因為她的兼職工作吧？
埃米：恐怕是，她工作過度，貪多嚼不爛啊。
艾倫：這也不能怪她，她經濟上有困難。
bite off more than sb.can chew例句精選：
You shouldn't bite off more than you can chew.
你不應該忙這麼多事。
Don't bite off more than you can chew.
不要貪多嚼不爛。
I mean, if we bite off more than we can chew, we'll lose everything.
我的意思是，如果我們非要打腫臉充胖子，我們將會失去所有。
I'm really afraid to bite off more than I can chew.
真怕我會做超出能力所及的事。
拓展學習：
overdo 使過勞
wade 費力做完
extreme 極限
capable 有能力的
keep one's nose to the grindstone 埋頭苦幹
be engaged in 努力從事…