... 結構中，不定式表示的“否定意味”。
too + 形容詞/副詞 to do：由於too 表達的程度，已經超過了極限，所以導致不定式的動作無法實現。意思是“太……以致於不能……”
如：It is too late to go now現在太遲了，不能去了。
反義問句（tag question）只對謂語動詞進行相反的提問，而不管其他成分。
鑑於這個理由，這類句子的反義問句應該是否定形式：
It is too late to go now， isn't it?
It’s too cold to go swimming today， isn't it?
He is too shy to speak to her，isn't he?
It’s too cheap to be good， isn't it?
He is too busy to see you now， isn't he?
He is too young to know right from wrong， isn't he?
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