谚语说“十雾九晴”，指大雾多发生在晴天时，因为()。

认知心理学家在研究推理、决策、问题解决等复杂认知过程时获得了很大的成功，主要原因是采取了（）手段。

The structural view limits knowing a language to knowing its structural rules and vocabulary. The　communicative or notional-functional view adds the need to know how to _____ the rules and vocabulary to do　whatever it is one wants to do.

《资治通鉴》成书于()。

我国的第二大盆地是()。