One day he saw an empty (空的) train and lie climbed (爬) in. It's lied no difficulty in starting it with his feet. goon the train was traveling at forty miles (英里) an hour. The railway officials (官员) could see tile boy in the wain and tried to stop the wain. The train arrived at a small station a little away from the town and then the boy drove it back. When he was near the town. a worker caught up with (追上) the train and stop it. At flint he was very angry (生气). hut he laughed when the boy said simply. "I like trains. "Well. I'm glad you don't like planes? the worker said.
An eleven-year-old boy wished lo he ______.
A.a plane driver
B.a train driver
C.a teacher
第2题
图示“M”型三位四通换向阀,其中位特点是:
A.P、O相通,A、B相通
B.A、B相通,P、O封闭
C.P、O相通,A、B封闭
D.P、O封闭,A、B封闭
第8题
与封闭型系统相比,开放型系统的特点是:
A.更多依赖特定卖方。
B.可移植性受到进一步的限制。
C.较廉价的组件。
D.互通性降低。
为了保护您的账号安全,请在“上学吧”公众号进行验证,点击“官网服务”-“账号验证”后输入验证码“”完成验证,验证成功后方可继续查看答案!