下列成语典故和传说中的相关的历史人物对应正确的一项是（ ）①望帝啼鹃　　　 ②苌弘化碧　　　③六月飞霜　　 ④亢旱三年

a good plan in theory, but it remains _______whether it works in practice.

301. In the middle of last century planes began to be used to transport both passengers and goods. The underlined words means ____.

We have jackets __________ all colors __________ 28 dollars.

Suchpoets as Shakespeare________widely read，of whose works，however，some_________difficultto understand