【 】是在输入或删除记录时，为维持表之间已定义的关系而必须遵循的规则。

请根据句意、括号中的中文提示或英文释义，写出句中所缺单词，使句子通顺。

1. Parents shouldn’t leave their babies         (单独) at home.

2. She was always         (紧张) about travelling by air.

3. My sister was born on         2nd, two days after Halloween.

4. Tom, would you         ( give a description of )your feelings of watching

Titanic3D?

5. Simply close your eyes and         deeply, and you will be calm and relaxed.

麦汁中的蛋白质在其（）时最不稳定，容易凝结析出。

阅读理解。

     Driving a large truck over mountain roads is not the usual way that a schoolteacher begins her day-

especially if she is a preschool teacher. But Mrs. Beth Miller does this five days every week. Her unusual

schoolhouse on wheels is actually a truck. The back of the truck has been made into a classroom in order

to carry the advantages of modern education to remote areas of the state of West Virginia. In many rural

areas of this state it is impossible for small children to go to regular schools because of the many hills and

valleys of Appalachian Mountains.

     The purpose of the schoolhouse on wheels project is to develop basic skills and social behavior in

children three to five years of age. This is done through games, exercises, toys and simple handcrafts. The

schoolhouse on wheels concept also teaches the young children to recognize 300 to 400 words on the printed

page. This is a great advantage in helping the pupils to learn to read when they begin regular school. In its

three-year history the project has helped about 350 children in an area made up of five counties, an area of

20 000 square kilometers. The schoolhouse on wheels is part of the Appalachian Educational Laboratory, a

research effort paid for by the government. Besides the mobile classroom, other parts of the program include

lessons by television and visits to the homes of the students. The technique is very effective, and one teacher

can do the work of seven in a traditional educational system. As a result the program costs about 50% less

than the regular kindergarten.

     All these advantages of the schoolhouse on wheels have made both parents and school officials happy.

West Virginia plans to increase the program and to include it in the public school system so that more than

4500 preschool children can have this valuable learning experience.

1. Mrs. Beth Miller usually _____.

A. walks to begin her work

B. drives a large truck to begin her work

C. drives her car to the school

D. carries the classroom to the school

2. Children in many rural areas of West Virginia cannot go to regular schools because _____.

A. large trucks cannot go in mountainous areas

B. there are no schoolhouses on wheels there

C. there are many hills and valleys there

D. preschool teachers don't like to work there

3. The best title for this passage is _____.

A. Schoolhouse on wheels

B. West Virginia

C. Effective educational system

D. Educational laboratory

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