真空钎焊主要用于（）材料的焊接。 A.低熔点 B.高硬度 C.易氧化

具有清肠凉血、疏风行气功效的方是

A．白头翁汤

B．槐花散

C．黄连解毒汤

D．十灰散

为了祖国统一和繁荣结成最广泛的爱国统一战线包括

①全体社会主义劳动者 ②社会主义事业建设者 ③拥护社会主义爱国者 ④拥护祖国统一爱国者

A、①②

B、①④

C、③④

D、①②③④

Everyone wants to be a pop star. When I was a kid, I wanted to be a pop star.   71   You get to sing and dance and make voices. People are willing to pay you tons of money and, of course, many fans love you. It’s a perfect life; what could be the problems?

  72  And one of the biggest problems is “crazy” fans who live their idols (偶像) too much. Andy Lau, the Hong Kang superstar, experienced that last year. A fan was so crazy about Andy that she persuaded her parents to spend all their money and travel to Hong Kang to meet him. Andy is a nice man so he met the girl and talked with her for a few minutes.

That should have been the end of the story, but it wasn’t!   73  In despair (绝望), the father jumped into the sea and said it was because Andy Lau had made him poor and had made his daughter a “crazy” fan. It’s a very sad story and it shows what can happen when ordinary people become crazy pop fans.

We like famous persons, and we enjoy listening to them.   74  And some people think that, since they love the pop star, the pop star should love then back.. That’s crazy!   75  They have their own families and friends. Their job is to entertain us, not to love us. So, don’t be a “crazy” fan, be a good fan, and just appreciate the joy, the happiness and the excitement that your favorite pop star bring you.

A．Well, clearly, there are lots of problems.

B．Sometimes we think we know them as well as we know our closest friends.

C．It seems like the coolest job in the world.

D．The family had spent all their money to meet Andy and they had no money to return home.E. They hated the superstar.

F. Pop stars have their own personal lives.

G. In fact, there is no difficulty in becoming a pop star.

将已沉淀澄清的原水的浊度进一步降低到小于5mg/L，需采用( )来处理。

A．机械加速澄清

B．水力循环澄清

C．离子交换器

D．过滤

热处理加工中正火处理方法（）（是、否）改变工件的化学性质？