问题 多项选择题

砼中掺速凝剂,下面说法正确的说法是()

A、掺入的目的是使砼早凝早强B、掺量一般为水泥重量的2%--4%

C、掺量一般为水泥重量的5%--6%

D、掺入量过多,延长凝固时间,起不到速凝作用

E、掺入量过少不起速凝作用

答案

参考答案:A, B, D, E

阅读理解

阅读理解。

     I have a love-hate feeling with 8 o'clock classes. I like to get started that early, but most students don't.

They usually came in late and looked sleepy at that hour.

     One day I was really angry at it. I was excited about the history lesson, but no one else seemed to be. I

wrote things on the blackboard. I moved around the room. I told stories. I tried humor (幽默). It was useless.

Their looks didn't seem to change. I was frustrated.

     I forgot to keep time. I was going to talk more when I looked down at my watch. It was already two

minutes past the end of class. So I just ended suddenly and soon the students began to pick up their book

bags and rushed out the door on their way to another class.

     While I was watching them leaving, I put away my own books, notes and papers. I took them up and

stepped out into the hall. I was tired and a bit sad. I had put everything I knew into that class and it had not

seemed to work. Then, as I started across the hall to my nearby office, a student came out the back door

of the classroom and caught up with me.

     Randy sat at the back of the classroom. I thought he wanted to ask why I didn't correct their exam

papers or maybe he wanted to ask for leave or… It was none of that. With his eyes sparkling (闪烁), Randy

said,"This is the first time I've not wanted a college class to end."

     The tiredness lifted. I had done better than I thought. I don't know if Randy will ever understand how

much he did for me that day.

1. The students usually came in late for 8 o'clock classes because __________.

A. they didn't like the teachers of 8 o'clock classes

B. they didn't understand the contents (内容) of the classes

C. they didn't like to get started that early

D. they didn't have any interest in the history lesson

2. I did what I could that morning to ___________.

A. tell them to make notes

B. show that I was a history teacher

C. talk as much as possible

D. make my class more interesting

3. I stopped talking suddenly because _________.

A. I had to look at my watch

B. the students had to go to another class

C. I was tired but pleased

D. the students were picking up things

4. When Randy came up to me, I thought ___________.

A. he might have some excuse for what

B. he did in class he wanted to help me carry things to my office

C. he had left something in the classroom

D. he would bring me something to eat

5. What did Randy's words mean to me?

A. He encouraged me a lot.

B. He was my best friend.

C. He was a top student.

D. He wanted to quarrel with me.

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