在越早形成的地层中，成为化石的生物越______，结构越______，在越晚形成

用所给词的正确形式填空，完成下面的故事。

      Last Monday, Ken and Ann went to a restaurant. They ____________ (sit) at a table. Ken was very

hungry. He looked at the menu. Ken ____________ (want) a hot dog and orange juice. Ken ____________ (eat)

his hot dog quickly. It was very hot. He ____________ (can) not breathe. He coughed and coughed. Ann

____________ (pat) him on the back and give him some orange juice. Soon he was better.

路边停车带是指设在车行道旁或路边的地面停车设施，指出下列( )是路边停车带的停车特点。

A．短时停车

B．全日停车

C．停车时间无一定规律

D．需设专用固定停车位

公安机关在社会治安综合治理中应该加强基层基础工作，坚持“打防并举、标本兼治、重在( )”的原则。

A．预防
B．治标
C．打击
D．治本

当采用交流弧焊电源时应选择（）焊条。

A.E4303

B.E4315

C.E5016、