密钥生成形式有两种：一种是（），另一种是由个人分散生成。

圆柱体体积=底面积×高，当体积一定时，底面积和高成______比例；当底面积一定时，体积和高成______比例．

根据所给词的适当形式填空（15分）

小题1:The scientist died in his ____________(forty). What a pity! He should be taken good care of.

小题2:The dresses ____________ (they ) are made of cotton, but they sell well because of the famous designer.

小题3:He has done his best to give his parents a _______ (surprise) answer.

小题4:Would you please help us describe one of the most famous ____________ (direct) appearance in English?

小题5:He told me that he _____________ (return) home before 6 o’clock, but he didn’t.

小题6:The price of houses _______________(rise) a lot in the past few years.

小题7:I don’t know if they ______________(show) around the History Museum yesterday.

小题8:The little boy often made everyone he knew __________ (play) with him together in the past.

小题9:There is a risk of being killed here, so we will move to another place for        (safe)

小题10:As an excellent teacher, she devoted most of her time to        (teach) her students.

小题11:___________, our planet, Earth is becoming more and more crowded.(sad)

小题12:Are you certain meals in the form of pills are much___________(taste)?

小题13:How many___________( toy) trains does your brother have?

小题14:At present, it may be difficult to imagine_______________(develop) the desert.

小题15:The reporter           the important conference between 8 a.m. and 10 a.m. yesterday. (cover)

识别真核基因启动子的是（）

A．σ70因子 

B．TATA盒结合蛋白（TBP） 

C．c端结构域（CTD） 

D．起始子（Inr） 

E．起始因子（IF）

下列有关苯妥英钠的叙述中，错误的是

A．可治疗某种心律失常

B．能引起牙龈增生

C．能治疗三叉神经痛

D．治疗癫痫大发作有效

E．口服吸收规则，t_1/2个体差异小

四刺辊开棉机属于（）。

A、握持打击开棉机

B、自由打击开棉机