Why Does Rain Smell So Good?

    Do you love the smell of rain? If so, you're not alone.

    {#blank#}1{#/blank#}(actual), some scientists believe that people got their love for the smell of rain from {#blank#}2{#/blank#}(ancestor), who relied on wet weather for their survival.

    But what makes rain smell so nice? There are several smells associated with rainfall that people find pleasing.

    One of these smells {#blank#}3{#/blank#}(call) “petrichor（尘土的味道）.” Petrichor, a term created in 1964 by two Australian scientists studying the smells of {#blank#}4{#/blank#}(rain) weather, comes from some chemical reactions.

    During dry periods some plants produce oils, and when it rains, these oils go into the air. Another reaction occurs when chemicals {#blank#}5{#/blank#}(produce) by some bacteria are sent out. All of these chemicals combine to create the pleasant particular smell when rain hits {#blank#}6{#/blank#} ground.

    Another smell associated with rain is ozone（臭氧）. During a thunderstorm, lightning can split oxygen and another gad and {#blank#}7{#/blank#}(it) in turn can combine into a new substance. This substance reacts with other chemicals to form ozone, {#blank#}8{#/blank#} has a sharp smell.

    When someone says he can smell rain coming, it may be that wind from an {#blank#}9{#/blank#}(approach) storm has carried ozone down from the clouds and {#blank#}10{#/blank#} the man's nose.

A: Hi, Lily! How about {#blank#}1{#/blank#}(go) to see a film together?

B: What time?

A: This Saturday evening.

B: I'm afraid I {#blank#}2{#/blank#}(can) go with you. So you'd better go there {#blank#}3{#/blank#}yourself.

A: Why? I {#blank#}4{#/blank#}(buy) two tickets already. This film is said to be very {#blank#}5{#/blank#}(interest). I had a lot of trouble in getting these two tickets.

B: I'm really sorry but I had made an{#blank#}6{#/blank#} (appoint) already. I'm going to see my former professor Lee at university this Saturday afternoon.

A: But can't you find some other time to see{#blank#}7{#/blank#}?

B: No, I can't. He is now {#blank#}8{#/blank#} (serious) ill in hospital.

A: Your teacher will be very happy {#blank#}9{#/blank#} (see) you.

B: I'm sure he will. He used to be very kind to us students {#blank#}10{#/blank#}we were at university. How about next Saturday? I will be free the whole day.

A: OK, let's make it next Saturday.

    How are you getting along with your high school? It may be hard for you as this is the first time that you {#blank#}1{#/blank#}(leave) your parents. I know that you are now having trouble{#blank#}2{#/blank#}(communicate) with others. That's{#blank#}3{#/blank#}you are new here and people don't know about you. But I think you can follow the advice below.

    First, you should take{#blank#}4{#/blank#}active part in the discussions and show your own opinions about the matters, and at the same time, learn to listen to other people's views{#blank#}5{#/blank#}(careful). Second, you should learn about your classmates' likes and dislikes,{#blank#}6{#/blank#}can make you get familiar with them. Only in this way can you get to know more{#blank#}7{#/blank#}(difference) people and show them that you are just as friendly. I'm always here ready to help. We can take part in some{#blank#}8{#/blank#}(activity) together and I can introduce you to others.

    There's no need{#blank#}9{#/blank#}(worry) too much. People will know you more very soon and will like to make friends{#blank#}10{#/blank#}you if you can do as the above.

    The Chinese invented block printing more than 1, 400 years ago. The original characters were carved on wood and ink was then applied. Block printing is time consuming and {#blank#}1{#/blank#} (cost) a lot of manpower and materials. Misprinted characters cannot be {#blank#}2{#/blank#} (easy) corrected. These shortcomings were only overcome after the appearance of movable type printing, {#blank#}3{#/blank#} greatly improved the speed and quality of printing.

    Bi Sheng of the Northern Song Dynasty invented the movable type printing. He carved the Chinese characters on small {#blank#}4{#/blank#} (cube) of sticky clay. He baked them in the fire until they became hard and movable. In the course of presswork, the movable characters were placed into {#blank#}5{#/blank#}, iron frame until it was full. He then took a smooth board and pressed it over the surface so that the block of type became even: Then ink was applied and it was ready {#blank#}6{#/blank#} printing. To be more {#blank#}7{#/blank#} (efficiency), he prepared two iron boards. When one was being used for printing, the other could be used {#blank#}8{#/blank#} (put) characters in order for the next page. The two boards were used alternately.

    Although what Bi Sheng invented was simple when {#blank#}9{#/blank#} (compare) to today's letterpress printing; it already bad the main traits of modem printing. So Bi Sheng's {#blank#}10{#/blank#} (contribute) to printing cannot be overstated.