问题 填空题

1806年英国化学家戴维用电解法从苏打中得到一种新金属.他对该金属做了以下实验:“取一块该金属,用小刀切下一块,把一小块金属投入水中,发生剧烈变化.它在水面上急速转动,发生嘶嘶声,并立即熔成一闪亮的银白色小球,并逐渐缩小,最后完全消失.”阅读后,归纳这种金属的物理性质

(1)______;(2)______;

(3)______;(4)______.

答案

(1)能用小刀切下一块说明金属较软.故填:质软.

(2)能浮在水面上说明金属的密度比水小.故填:密度小于水.

(3)熔成一闪亮的银白色小球说明金属是银白色的.故填:银白色.

(4)立即熔成一闪亮的银白色小球说明金属的熔点低.故填:熔点低.

单项选择题
阅读理解

Do you think it is ever a good idea for a teenager to have a credit card?

My kids watch closely as I swipe the card through the register.They’ve seen me do it hundreds, thousands of times.Cool.They are itching to swipe it through the machine themselves. When we walk out of the store with our groceries or pet food, or whatever, it’s almost as though money has not changed hands, painless, easy.

So it shouldn’t be shocking to discover that teenagers are becoming card carrying consumers in their own right.The question is, should they?

While some argue it’s best to teach kids how to use a credit card while still living under the family roof, not everyone agrees. Dave Ramsey, financial expert says getting a credit card for your teenager is actually, “an excellent way to teach him or her to be financially irresponsible.”

Now parents are required to co-sign on credit cards for children under 21.“If their name is on the credit card, then the parent may say, ‘Hey, my name is on this.Don’t get me into trouble,” says Mary Beth Pinto, a marketing professor.“When parents were the co-obligors(共同借贷人),the children caused less debt.If the parents are the co-obligors, the tendency is that the parents were explaining how to use the cards.” Still, Pinto believes parents should start the process much earlier.“Yes, there has to be teaching going on and it has to start when they’re younger. You’re not going to get rid of credit cards.They are here to stay. You have to have them. You can’t fight progress,” Pinto said.

Ramsey, however, disagrees.“Throwing teens into a pool of (credit)sharks is a sure way to guarantee a life-time of heartache,” he said.“You can make online purchases and rent a car with a credit card.Of course, you must have money in your bank account before you can make a purchase with a credit card.But paying for things with money is what you are supposed to do.”

小题1:The author mentioned her experience in Para 2 mainly to______.

A.prove the convenience of using credit cards

B.tell what impression credit cards leave on kids

C.give advice on using credit cards wisely

D.explain the pleasure credit cards bring to customers小题2:The underlined word in Para 2 can be replaced by __________.

A.eager

B.afraid

C.embarrassed

D.thankful小题3:What’s Ramsey’s attitude towards teens’ using credit cards?

A.He feels it is worth a try

B.He is very supportive

C.He is strongly against it

D.He considers it as a pleasant experience小题4:Pinto will most likely agree that __________.

A.parents should let teens own their credit cards earlier

B.you shouldn’t be in control of credit cards

C.it is never good for anyone to get a credit card

D.learning to use credit cards is practical