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        1. Robert knows that healthy, well-watered plants are quiet. He also knows that many insects prefer attacking dry plants rather than healthy plants. How do the insects know which are healthy plants and which are not? Robert thinks that the insects may hear the plants crying and then they may come to kill. . 56. There are many "water pipes" . A. in a plant's stemB. in a plant's peelC. in a plant's barkD. in the earth 查看更多

           

          題目列表(包括答案和解析)

            We all cry for water when we are thirsty. But do you know, in very hot, dry weather, plants also make very low sounds-as if they are crying out for help?

            You see,in a plant's stem(莖)there are several hundred water pipes (管道)”that bring water from soil all the way up to the leaves. When the ground turns dry, it becomes harder and harder for plants to do this.

            In very hot days, plants have to get any water that it can. Scientist Robert Winter has found out that when plants can get no water, their water pipes snap (發(fā)出斷裂聲). When that happens, the whole plant vibrates (振動) a little.

            Robert knows that healthy, well-watered plants are quiet. He also knows that many insects (昆蟲)prefer attacking dry plants rather than healthy plants. How do the insects know which are healthy plants and which are not? Robert thinks that the insects may hear the plants crying and then they may come to kill it.

          (1)There are many water pipes_________.

          [  ]

          Ain a plant's stem

          Bin a plant's peel(果皮)

          Cin a plant's bark(樹皮)

          Din the earth

          (2)When plants can, ________, their water pipes snap.

          [  ]

          Agrow well

          Bget no sunlight

          Chave enough water

          Dget no water

          (3)When water pipessnap, the whole plant ________.

          [  ]

          Akeeps quiet

          Bvibrates a little

          Cgets well

          Dmakes very loud sounds

          (4)Many insects like to attack ________.

          [  ]

          Aquiet plants

          Bdry plants

          Chealthy plants

                Dwell-watered plants

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          閱讀理解

          閱讀下面短文,短文后有五個理解性的題目,在各題所給的(A)、(B)、(C)、(D)四個選項中,選出一個最佳選項,并把答案涂在答題卡里。

            We all cry for water when we are thirsty. But do you know, in very hot, dry weather, plants also make very low sounds-as if they are crying out for help?

            You see, in a plant's stem(莖) there are several hundred “water pipes(管道)” that bring water from soil all the way up to the leaves. When the ground turns dry, it becomes harder and harder for plants to do this.

            In very hot days, plants have to get any water that it can. Scientist Robert Winter has found out that when plants can get no water, their “water pipes” snap(發(fā)出斷裂聲). When that happens, the whole plant vibrates(振動) a little. The snapping pipes make noises ten thousand times more quiet than a whisper(低語).

            Robert knows that healthy, well-watered plants are quiet. He also knows that many insects(昆蟲) prefer attacking dry plants rather than healthy plants. How do the insects know which are healthy plants and which are not? Robert thinks that the insects may hear the plants crying and then they may come to kill.

          1.There are many “water pipes” ________.

          [  ]

          A.in a plant's stem
          B.in a plant's peel(果皮)
          C.in a plant's bark(樹皮)
          D.in the earth

          2.When plants can ________, their “water pipes” snap.

          [  ]

          A.grow well
          B.get no sunlight
          C.have enough water
          D.get no water

          3.When “water pipes” snap, the whole plant ________.

          [  ]

          A.keeps quiet

          B.vibrates a little

          C.gets well

          D.makes very loud sounds

          4.The snapping pipes make noises ________ times more quiet than a whisper.

          [  ]

          A.l00
          B.1,000
          C.l0,000
          D.l00,000

          5.Many insects like to attack ________.

          [  ]

          A.quiet plants
          B.dry plants
          C.healthy plants
          D.well-watered plants

          查看答案和解析>>


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