人们早已知道，如果材料的表面积足够大，可引起催化反应。It had been known for some time that chemical reactions can be catalyzed by materials with large surface areas.它们对被它们催化的反应有很强的专一性.They are highly specific for the reactions that they catalyze.在...
He picked up a pencil and toyed with it idly.他捡起一支铅笔，无所事事地摆弄着。He toyed with the idea of going to China.他动过去中国的念头，但并没当真。While he was talking to his secretary, he toyed with a pencil.在和秘书谈话的时候, 他手中摆弄着一支铅笔....
I think you ought to give football a rest for a time.我认为你应该暂时停止踢足球。Things were pretty grim for a time.事情一度糟糕透了。After reflecting for a time he decided not to go.思考了一会儿以后,他决定不去了....
Although basically an engine hood AOL continues to include certain differences.尽管从根本上说,IE是 AOL的默认浏览器,但它包含不同的种类.Go to a site like Yahoo! Finance and enter 'AOL' in the Get Quotes field.登录诸如“雅虎财经”这样的站点，在“股票行情”栏输入...