You may have heard of Niagara Falls（尼亚加拉大瀑布), but do you know about the Niagara Escarpment(断崖)?It's a long steep slope(陡坡){#blank#}1{#/blank#}runs through the US and Canada. Earlier this month, our school went on a hiking trip to this beautiful place.

    The weather was cold, cloudy and windy, so we wore more{#blank#}2{#/blank#}(stay)warm. We{#blank#}3{#/blank#}(divide)into two groups and went on different routes(路线). The whole escarpment is 725km long. But we only covered 8km for about four{#blank#}4{#/blank#}(hour).

    My favorite part of the trail(dx道)was the cave(山洞). The cave was formed from many different shaped rocks. Some were huge while the{#blank#}5{#/blank#}were small. We climbed down into the rocks{#blank#}6{#/blank#}the help of our teachers. The rocks were steep and slippery(滑的)because they were wet. It was{#blank#}7{#/blank#} exciting experience for all of us.

    After{#blank#}8{#/blank#}(walk)5 km without any rest, we were hungry and tired. {#blank#}9{#/blank#}our teacher finally said we could stop to have lunch, we were very excited. After all, this trail was a little different from the ones I'm used to. It was{#blank#}10{#/blank#}(natural)than before.

    Over millions of years ago, there were no deserts. Now about three tenths of the Earth's surface{#blank#}1{#/blank#} deserts. The size of the world's deserts is always {#blank#}2{#/blank#} (change). Deserts can be hot or cold. The Australian Desert is a hot desert, while the Gobi Desert in Mongolia is an example of a cold desert. Deserts are dry areas {#blank#}3{#/blank#} less than 50 cm of rain falls each year. The Sahara Desert in Africa receives less than 1.5 cm a year. {#blank#}4{#/blank#} rain doesn't fall very often in deserts, sometimes even for years, there can be heavy rain {#blank#}5{#/blank#}(sudden). Because they are dry, deserts have wide changes in temperature each day. When the sun {#blank#}6{#/blank#}(go) up, it is very hot. At night, the heat {#blank#}7{#/blank#} (receive) by the ground during the day {#blank#}8{#/blank#} (quick) disappears (消失), and then it becomes very cold. Because{#blank#}9{#/blank#}the change, living in the desert is very difficult. Man can make deserts, but they can also stop them from getting larger and larger. Planting trees can prevent the sand from{#blank#}10{#/blank#}(spread).

    In today's world, more and more people know noise is also a kind of pollution and is harmful {#blank#}1{#/blank#}human's health.

    People who work and live in noisy conditions go deaf {#blank#}2{#/blank#}（easy）. For example, many of the workers{#blank#}3{#/blank#}print newspapers and books go deaf. Quite {#blank#}4{#/blank#}few people living near airports also have hearing problem. Recently, it {#blank#}5{#/blank#}（report） that many teenagers in America can not hear well {#blank#}6{#/blank#}these young people always listen to loud pop music.

    Loud noise in public is also a kind of pollution. It not only disturbs others {#blank#}7{#/blank#}also hurts people's hearing. Cars and machines also produce too much noise. Such pollution makes people feel uncomfortable or unpleasant, and it can even cause them {#blank#}8{#/blank#}（become） deaf. {#blank#}9{#/blank#}terrible!

    Nowadays, many countries are trying to solve noise pollution. So {#blank#}10{#/blank#}（not） make loud noise in public, or you may be punished by the government!

    Today is Miss Li's birthday. She is thirty years {#blank#}1{#/blank#} She is {#blank#}2{#/blank#} (we) maths teacher.  She is a very kind teacher in our school and we love {#blank#}3{#/blank#} very much. We send lots of {#blank#}4{#/blank#} to her. The cold winter is coming, so I buy a red scarf {#blank#}5{#/blank#} her. She likes it very much. Some of my {#blank#}6{#/blank#} (classmate) buy flowers for her. She {#blank#}7{#/blank#} (see) many flowers on her desk when she comes into the classroom.

    We have {#blank#}8{#/blank#} birthday party at night. We sing a birthday song and dance for her. She also {#blank#}9{#/blank#} (play) games with us. We {#blank#}10{#/blank#} (be) very happy!