One day, a lobster(龙虾) met a hermit crab(寄居蟹)in the deep sea. They stopped {#blank#}1{#/blank#} (swim) and began to have a talk with each other.

    The lobster {#blank#}2{#/blank#} (take) off his hard shell and showed his lovely and soft body. When the hermit crab saw the lobster take off the shell, {#blank#}3{#/blank#}felt surprised. He shouted at the lobster and wanted to stop the lobster.

    "Hey!" said the crab. “{#blank#}4{#/blank#} are you talking off your shell? The shell is {#blank#}5{#/blank#} (use) and it can protect you. Now you take off your shell. Big fish may eat you. You may also knock against a rock. Don't be silly. Please put {#blank#}6{#/blank#} your shell again. Or you will have to {#blank#}7{#/blank#} (payment) a heavy price for what you did."

    “{#blank#}8{#/blank#} (thank) for your reminding, hermit crab! But we take off our shells in order {#blank#}9{#/blank#} (grow) better. {#blank#}10{#/blank#}we are afraid to take off our shells, then we can't move forward in life," answered the lobster.

    The hermit crab thought it over and understood what the lobster said.

    Our desks and chairs {#blank#}1{#/blank#}(make) of wood. The paper of books and newspapers {#blank#}2{#/blank#}(make) from wood, too. Wood is important in our daily life.

    Where does wood come from? It {#blank#}3{#/blank#}(take) from trees which grow in the mountains. Do you know how it {#blank#}4{#/blank#}(carry) to us from the mountains?

    First of all, trees {#blank#}5{#/blank#}(cut) down when they {#blank#}6{#/blank#}(grow) big enough. Then their branches {#blank#}7{#/blank#}(cut) off, and logs(原木) {#blank#}8{#/blank#}(make). These heavy logs {#blank#}9{#/blank#}(put) together in different ways and {#blank#}10{#/blank#}(take) down to the foot of the mountains.