在 There be句型中 There is no smoke without fire There seems to be little time left There,here结构中,如果主语有好几个,谓语动词 与最邻近的主语一致。 There was a TV set, a portrait and several albums on the shelf

1. If you had come earlier, you the famous scientist a could be met b. might meet c would have met d. would meet

1. for the people is a glorious death. a. To die b.Dead c. To be died d. Being died

1全部倒装( Full Inversion,又称主谓倒装 (Subject-verb Inversion) 例如: Here are some letters for you Down poured the rain Into the coach scrambled the children

后接动名词作宾语的常用动词有: admit advise allow anticipate appreciate avoid risk delay deny dislike dread 后接动名词(或名词)作宾语的常用短语

till after, from behind, except in We stayed there till after the sunset He picked up the gun from behind the counter The weather has been fine except in the north

情态动词( model verb)用来表示能力 允许、可能、必须、劝告、意愿等概念或态 度。主要的情态动词有can( could),may might), shall(should), will (would) must, ought to,ned,dare等。情态动词没有 人称和数的变化,其后常跟不带to的不定式

三种基本形式 If had a bike.I would lend it to you(f从句用过去时,主句用 should/ would/ could/ mighti不定式) If he had been here he would have helped you(从句过去完成时,主句 should would/ could/ might+不定式完成时) I would do it some other wa(从句用 should/ were to3主句用 should/woud could /might+不定式)

原子发射光谱法,是利用物质在热激发或电激 发下,每种元素的原子或离子发射特征光谱来 判断物质的组成,而进行元素的定性与定量分 析的方法

本讲主要学习气相色谱的基本理论 以及气相色谱仪器和气相色谱的基 本应用