【单选题】拆开发电机的定子绕组与硅二极管的连接线,用万用表R×1挡逐个检查交流发电机每个硅二极管,将万用表两极测棒分别接在二极管的两极上检测一次,交换两表笔的位置再测一次。若两次测得均为∞,则该二极管( )。
【单选题】拆开发电机的定子绕组与硅二极管的连接线,用万用表R×1挡逐个检查交流发电机每个硅二极管,将万用表两极测棒分别接在二极管的两极上检测一次,交换两表笔的位置再测一次。若两次测得阻值均为零,则该二极管( )。
【单选题】Unit 2-Short passage What was the speaker doing when a customer walked in one morning?
A.
Planting some trees in the greenhouse.
B.
Writing a want ad to a local newspaper.
C.
Putting up a"Going Out of Business"sign.
D.
Helping a customer select some purchases.
【单选题】book4unit2 Passage 1 Listen to a short passage and choose the best answer to each question you hear.
A.
They live their whole lives in a mountain
B.
They live to a much older age
C.
They have high expectations for life
D.
They seek doctors' advice more often
【单选题】拆开发电机的定子绕组与硅二极管的连接线,用万用表R×1挡逐个检查交流发电机每个硅二极管,将万用表两极测棒分别接在二极管的两极上检测一次,交换两表笔的位置再测一次。若两次测得阻值均为一大(10千欧)一小(8~10 欧),则该二极管( )。
【单选题】Unit 2-Short passage What did the speaker think of when serving the office manager?
A.
Opening an office in the new office park.
B.
Keeping better relations with her company.
C.
Developing fresh business opportunities.
D.
Building a big greenhouse of his own.
【判断题】客房服务员进客房前,先敲门,应站在距房门约0.5米远的地方。
【判断题】定子绕组短路与断路检查。用万用表检测定子绕组4个接线端,两两相测
【单选题】Unit 2-Short passage What do we learn about the greenhouse?
A.
It was located in a park.
B.
Its owner died of a heart attack.
C.
It went bankrupt all of a sudden.
D.
Its potted plants were for lease only.
【单选题】Unit 2-Short passage What was the speaker's hope for the future?
A.
Owning the greenhouse one day.
B.
Securing a job at the office park.
C.
Cultivating more potted plants.
D.
Finding customers out of town.