I am always eager to do experiments, especially chemistry ones. It's   _26_  to work with test tubes and beakers（烧杯） , even though sometimes my efforts end in__27___. Experiments were fun for me  __28  a recent accident.

The   29  happened when I was heating a big test tube with an alcohol burner（酒精灯） , chatting to my partner while waiting for__30____ changes. All of a sudden, the tube cracked. Even though I jumped from my seat when I heard the crack, the hair on my forehead was __31____ as I was leaning too close to the test tube.

  __32___ I had no time to be sad about my hair: the liquid in the test tube poured onto the table and caught fire. I'd never  33 _ anything so bad! My___34___went blank （空白）for a moment. Then I quickly covered the fire with a damp cloth to__35____.

The teacher told me that the test tube broke in half at the bottom because we didn't dry it properly before __36___ it.

We calmed down and did the experiment, again. But our hearts were still __37____ rapidly even after we walked out of the lab.

But my bad __38___ didn't end there! Since all __39     was focused on the flames while we were in the lab, I didn't see the liquid falling onto my trousers.

During the following class, I felt a __40___ in my leg. Soon it became more and more painful and I touched the area with my fingers,   _41_  to make things better. But to my great    42___ , the material of my trousers turned into powder! “Vitrio（硫酸）! ! !”The terrible word came into my mind. I rushed out right away to wash and examine my poor skin.  _43_  , it was not a serious injury.

After changing my __44____I sat down and told myself: danger is no joke! It's very important to have a serious___45___ in chemistry class. Doing scientific experiments as a learner is no laughing matter.

1.	A．exciting B．moving C．dangerous D．difficult

 

2.	A．success B．failure C．loss D．waste

 

3.	A．but B．except C．besides D．until

 

4.	A．incident B．change C．disaster D．accident

 

5.	A．physical B．chemical C．biological D．historical

 

6.	A．broken B．burnt C．blown D．pulled

 

7.	A．And B．Instead C．But D．Or

 

8.	A．felt B．heard C．experienced D．imagined

 

9.	A．head B．stomach C．ear D．mind

 

10.	A．leave it out B．let it out C．give it out D．put it out

 

11.	A．boiling B．holding C．heating D．cooking

 

12.	A．striking B．beating C．knocking D．hitting

 

13.	A．feeling B．time C．chance D．luck

 

14.	A．effort B．sense C．attention D．spirit

 

15.	A．push B．pain C．bite D．touch

 

16.	A．failing B．managing C．trying D．planning

 

17.	A．disappointment B．joy C．surprise D．comfort

 

18.	A．Fortunately B．Obviously C．Unexpectedly D．Generally

 

19.	A．coats B．shirts C．socks D．trousers

 

20.	A．heart B．attitude C．thought D．preparation