1.       If we did not have air, there would be no sound.
  Without air, there would be no life.
  2.       not…but…不是…而是…连接并列状语
  eg: In the past three years, he did not study for his doctoral degree, but worked to support his family.
  3.       not 用在代词all, both, every(thing,body)和副词always, necessarily¹, quite, altogether等词之前，表示部分否定.
  Eg: I don’t know both of them.
     Both they are not here.
     All men are not honest.
     Not everybody like reading.
  4.       It+takes+somebody(宾格)+时间(金钱，等)+to do 花费时间，金钱等去做某事。
  Eg: It took him five minutes to solve the problem.
  It takes many hands to do the work.
  It took me 150 dollars to buy this coat.

LESSoN SIX    TEXT  B
      The Difference Between plants And Animals
      If you were asked, What is the difference between a plant and an animal? what answer do you think you would give? Your first thought might be that a plant has leaves and roots and flowers, which an animal has not. Yet that would not be correct; for there are many plants which have neither roots nor leaves nor flowers, while there are some animals which seem to have all three.
      Look up into the sky, and then down at the earth beneath your feet. It is easy enough, you think, to tell which is earth and which is sky; but if you live in the wide, open country, or near the sea, you will often find when you look far away to the place where sky and earth seem to meet, that this is a matter of some difficulty². You see only the thin blue haze³, like smoke, which is the dividing line between the heavens and the earth. But just where the one ends and the other begins, you cannot tell.
   
      Just so it is throughout⁴ all the world of Nature. You may look at a group of cows standing⁵ under the trees or catch a bee at his early drink in a morning-glory bell, and you would laugh if any one should ask you whether you can tell an animal from a plant.
  But suppose you turn aside from these familiar, everyday things, and study objects which you have to look at through a magnifying⁶ glass, and you will find many things that will puzzle you. You will find plants without roots, leaves, flowers, or seeds; and you will find animals without heads, legs, eyes, mouths, or stomachs.
   
  Foggysunny ainysnowywindy
  Set aside o turn aside from
  Confuse---confused---confusing
  puzzle----puzzling----puzzled
  Melon-seeds
  observe---observer---observation
  Watch
  Latter
  Dweller
  Narrow-------wide
  Taste delicious
  The ice-cream tastes delicious.
  The idea sounds good.
  Close---open
  Shut  up
  Suck in
  Be dissatisfied⁷ with
  Happen occur
  This animal lives on grass.
  Take over----hand over
  ofamong
  Tell a from b distinguish
  Tell a story
  Tell a lie
  Heaven and hell⁸.
  If I were you , I would go abroad.