将下列各句变为被动语态（可以省去动作执行者）. 1. The USA Acade

误差不可以______，但是可以______，对此常采用的方法是：______．

阅读理解。

     A lift is wonderful. It is really only a small room. Rooms usually stay in one place. Lifts travel up and

down all day long.

     Sometimes a worker stands in the lift. He or she operates it up and down. In modern lifts there is no

worker. The people walk in. They know what floor they want. They push a button and the lift goes to

that floor. It is all very fast and easy.

     Lifts are very important to us. Why? Think about a tall building. Maybe it has twenty floors. Maybe it

has fifty or more. Who can walk up all the stairs? Maybe people can climb them one time. Can someone

climb thirty floors to an office every day? Can small children walk up to their room on the twenty-fourth

floor? Can their mother and father carry food up all those stairs? Of course not.

      We can have high buildings because we have lifts. We could not have all the beautiful tall buildings in

the world without lifts. They are really wonderful.

1. A lift looks like ______.

A. a small room

B. a small house　　

C. a small ladder　　

D. a small stair

2. Which of the following is true?

A. A modern lift has no buttons.

B. A modern lift has a worker to operate it.

C.A modern lift can go up and down with no worker in it.

D. A modern lift knows what floor people want.

3. If you want to go to the floor you want, you_______.

A. ask for help

B. open the door of the lift

C. ring the bell 　

D. push the right button

25岁，孕1产1，由于滞产压迫致尿瘘，漏尿开始出现时多是在（）

A.产后10～14天

B.产后3～7天

C.分娩后立即出现

D.产后1个月

E.产后2个月

客户赎回基金，按照法规要求多长时间必须支付投资者款项（）

A、T+1

B、T+3

C、T+5

D、T+7

关于重油制气工艺存在的问题，下列描述错误的是（）。

A.渣油凝固点较高，一般为25～45℃，所以需在储存及输送中采用蒸汽伴热或套管保温

B.渣油黏度高，100℃下恩氏黏度最大可达20，为了满足喷嘴所需的最佳雾化黏度，需预热至120℃或更高

C.重油或渣油C／H比较大，一般为120左右，在裂解成为碳氢比约为30的城市煤气过程中就生成了大量焦油、积炭，在煤气急冷降温时，焦油、部分积炭溶于水中，污染了循环水，加大了循环水及污水处理难度

D.制气炉出口的荒煤气温度最高达到500℃，只因燃气中含有大量的焦油、苯、萘等杂质，不能应用废热锅炉回收显热，热效率低