We must be practical and thecost we make a decision. [ ]

John was heard ________ just now. What happened—People was telling a joke.

依次填入下列各句横线处的成语，最恰当的一组是：① 都说“三百六十行，行行出状元”，这话不假。青年人经过专业化的学习，都会成为 _________，所以不必鄙视职业技术学院的毕业生。② 三人当初合资创办企业的时候投入资金多少差异很大，所以在年终分红之时就有人提出来不能_________，要有所区别。③ 清华大学偏工程性、技术性、应用性，所以清华大学工程院院士多；北京大学偏理论性、科学性、基础性，所以北大科学院院士多。两所大学都是国内顶尖级的，_________ 。

I have not seen him_____ he went tocollege

You’re coughing badly, Martin．Why not give up smoking?—- Give up smoking? Easier said than done, Amy．Once you _____ the habit of smoking, it is very hard for you to______．