24. ________ that forty percent of the oxygen of the world is produced in theAmazon rainforest.(A) I
25. ________ of oxygen and hydrogen, which are two of the trace elements in air.(A) Water being comp
27. Amphibians are cold-blooded animals whose body temperature varies withtheir surroundings, and mo
29. Some __________ animals like giraffes, okapis, and cattle can extend theirtongues all the way to
30. _________ unwilling to do so, he had to follow the traditional ways of doingthings.(A) Because (
31. Taxonomy is a scientific method which deals with __________.(A) all living things are classified
33. Some species of baby fish are _______ tiny and transparent that they arealmost invisible.(A) too
34. Mangroves are tropical plants that live in the intertidal zone where sea waterand fresh water ar
35. Most psychologists deeply believe that it is just as difficult to change aperson’s way of thinki
36. Organ transplants are the most difficult jobs _________ the surgicaloperations.(A) except (B) fr
37. The size of birds _________ on their ability to fly, for weight increases itsburden when it take
38. Medical research indicates that alcohol and caffeine can make the stomachmore sensitive to the _
39. Some marine fish can excrete salt by means of _________of special cells inthe gills and intestin
40. Aspirin is used to __________ the effect of pains, such as headache,toothache, and sore throat.(
41. I want to go to the dentist, but you _______ with me.(A) do not need go (B) need not to go (C) n
43. The process _______ plants to transform solar energy into food is calledphotosynthesis.(A) it en
44. Some plants have obvious distinctive features for us to tell them apart at thefirst sight, while
46. With the outbreak of SARS, how to control this highly contagious disease hasbecome a major _____