我国古代就有许多发明和创造．下列叙述中不涉及到化学变化的是（_爱下问搜题

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问题选择题

我国古代就有许多发明和创造．下列叙述中不涉及到化学变化的是（　　）

A．烧制陶瓷

B．制作石器

C．粮食酿酒

D．使用火药

答案

A、烧制陶瓷的主要原料是粘土，陶瓷成分主要是氧化硅、氧化铝等，所以制陶瓷的过程中有新物质生成，属于化学变化．故选项错误；

B、制作石器的过程中只是形状发生改变，没有新物质生成，属于物理变化．故选项正确；

C、粮食酿酒的过程中有新物质酒精生成，属于化学变化．故选项错误；

D、使用火药的过程中有新物质二氧化碳、二氧化硫等生成，属于化学变化．故选项错误．

故选B．

填空题

依据不同的角度，决策可以分为不同的类型和方法，依工作者本身的角色可将决策分为咨询式决策、（）、协助式决策、威胁式决策。

完形填空

“Now ,”Mrs. Virginia DeView said, smiling, “we are going to discover our professions .”
The class seems to be greatly surprised. Our professions? We were only 13 and 14 years old! The teacher must be _36 _. “Yes, you will all be searching for your future  37 . Each of you will have to   38 someone in your field, plus give an oral report.”
Each day in her class, Virginia DeView reminded us about this. Finally, I picked print journalism. This _39_ I had to go to interview a true-blue newspaper reporter. I was extremely nervous. I sat down in front of him_40_ able to speak. He looked at me and said, “Did you bring a pencil or pen?”
I shook my head. “How about some   41_ ?” I shook my head again .
Finally , I thought he realized I was   42 , and I got my first big tip as a 43 : “Never,never go anywhere without a pen and paper. You never know what you’ll run into. ”After a few days, I gave my oral report totally from   44  in class. I got an A on the entire project.
Years later, I was in college looking around for a new career, but with no success. Then I _45 _Virginia DeView and my desire at 13 to be a journalist. And I called my parents. They didn’t __46__me. They just reminded me how competitive the field was and   47  all my life I had to run away from competition. This was true. But journalism did something to me; it was in my blood. _48__gave me the freedom to go up to total strangers and ask what was   49 .
For the past 12 years, I’ve had the most satisfying reporting career, __50 __ stories from murders to airplane crashes and   51 choosing my strongest area. 52 _ I went to pick up my phone one day, an incredible wave of memories hit me and I realized that had it not been __53__Virginia DeView, I would not be sitting at that desk.
I get 54 all the time: “How did you pick journalism?”
“Well, you see, there was a teacher…”I just wish I could 55 her.

C．professions

C．preparations

B．comfortable

C．imagination

B．Virginia DeView

D．My oral report

A．breaking in

B．getting down

C．falling off

B．listening to

D．On condition

C．disappointed