30What does the author intend to tell us by describing how he accepts the invitation of the local television station?

48.We should try our best to preserve our natural land so that future generations may also truly immerse themselves( )the experience of its natural beauty.

47. Of course, there will be people you can call on for help from time to time, but basically you are ( )your own, and you have to develop an inner source of strength and self-reliance that you may not feel.

46. It is understandable that the health and Vy welfare of their family is an ( )concern for this young couple.

45. The movie presents Lincoln as a strong-willed, ( )man who led the US through a moral, constitutional and political crisis.

44. He received an ( )call threatening to disclosexletails of his affair if he didn't pay the money.

43. In the( )of research, it is an accepted fact that scientific publications have to be written or translated into English to get published, acknowledged, and cited.

42. Praise must be used wisely to ( ) students who perform up to expectations and to encourage students to perform to maximum levels.

41.The director said that they needed a young actress who could ( )someone who was both unbalanced and confident at the same time.

40. The results of the survey are ( )and useful despite being from a small sample.

39. He has been ( )by a horrible disease. from wftich one of his best friends died two weeks ago.