低比转数的离心泵适用于（）场合。A、大流量高扬程 B、大流量低扬程 C、小流量高扬程

世界上一切物体都在               ，绝对静止的物体是              的．

打击是落实综合治理的关键。( )

A good way to pass an exam is to work hard every day in a year．You may fail in an exam if you are lazy for most of the year and then work hard only a few days before the exam．If you want to be good at English, you have to read stories in English and speak English as much as possible．A few days before the exam you should go to bed early．Do not go to bed late at night studying. Before you start the exam, read carefully over the question papers.Try to understand the exact meaning of each question．When you have finished your exam, read over your answers．Correct the mistakes if there are any and be sure that you have not missed anything out.

56．If people want to do well in an exam．they have to work hard         ．

A．every day in a year．        B．for most of the month

C．for only a few days          D．late at night

57．If people want to learn English well, they          .

A．only need to learn grammar    B．must often practise English

C．have to go to England         D．should go to bed early

58．It’s important to          a few days before the exam．

A．play too much               B．have a good sleep

C．read the question papers       D．have a good drink

59．The best title for the passage is         

A．An Important Exam           B．An Easy Exam

C．Get Ready for an Exam        D．How to Pass an Exam

男性，65岁，因下前牙急性骨膜下脓肿就诊，第一次的处理如下，除外（）

A.开髓拔髓

B.荡洗封药

C.根管机械预备

D.脓肿切开引流

E.消炎和止痛药

用带有绝缘手柄的电工钳或绝缘手柄的斧头切断带电导线，使触电者脱离电源时，应从电源侧同时切断两根导线。（）