[填空题]When (heat) ______ , iron can be changed into liquid.

[填空题]When (heat)（）iron can be changed into liquid.

[填空题]When (heat) （　）, water can be changed into vapour.

[填空题]When (heat) ______ , water can be changed into vapour.

[填空题]When (heat)（）, ice will be changed into water.

[填空题]Infrared radiation can produce heat ______.

[单项选择]This kind of material can ______ heat and moisture.
A. delete
B. compel
C. constrain
D. repel

[单项选择]Pig iron, wrought iron, and steel contain iron carbides made up of ______ of carbon.
A. amounts are different
B. different amounts that
C. different amounts
D. which amounts are different

[单项选择](A) heat exchanger is a device (in) which (heat taken) from a hot liquid or gas in order to warm a (cold place).（）
A. A
B. in
C. heat taken
D. cold place

[简答题]The domestic iron and steel producers found themselves ______(正在同世界上的跨国公司争夺潜在客户).

[单项选择]1 David Smith worked primarily in iron, exploring its possibilities more fully than any other sculptor before or since. To Smith, iron spoke of the power, mobility, and vigor of the industrial age. Smith was born in Indiana in 1906, the descendant of a nineteenth- century blacksmith. His iron sculptures flowed naturally out of the mechanized heart of America, a landscape of railroads and factories. As a child, Smith played on trains and around factories, as well as in nature on hills and near creeks. He originally wanted to be a painter, but after seeing photographs of the metal sculpture of Picasso in an art magazine, he began to realize that iron could be handled as directly as paint.
2 Many of Smith’s sculptures are "totems" that suggest variations on the human figure. They are not large iron dolls, although several have "heads" or "legs." Still, they forcefully convey posture and gesture. Their message flows from the internal relations of the forms and from t
A. He gained experience while working in a blacksmith factory.
B. His childhood exposed him to the uses and possibilities of iron.
C. His early sculptures revealed his desire to be a landscape painter.
D. He first learned about metals by seeing pictures in a magazin