预制工程是在有良好的机械设备的管道加工厂内进行的。
参考答案:对
经消化道传播的疾病是()。
A.麻疹
B.百日咳
C.中毒性细菌性痢疾
D.流行性乙型脑炎
E.流行性脑脊髓膜炎
根据所学课文内容填空
At first my new 1 were difficult to tolerate. The air seemed thin, as 2 its combination of gases
had little oxygen left. 3 by a lack of fresh air, my head ached. Wang ping handed a mask to me
and I felt better in 4 time. Soon I was 5 on my feet again and following him to collect a hovering
carriage driven by computer. Wang Ping 6 my safety belt and showed me how to use it. Soon I
could fly as fast as him. However, I lost 7 of him when we reached 8 looked like a lager market
because of too many carriage flying in all directions.