60. Cyclists complain about their morning battles with the increasing number of motor v_____.

59. He is a green hand. He has had no p______________ experience of this kind of job.

58. This is a p______________ land, and you can’t walk across it without permission.

57. We’ll be sitting in the second c_________________ from the bottom of the train.

56. It’s not easy to m______________ a foreign language.

55. Animals in zoos are not in their natural s_______________.

54. S_______________ at birth, the twins do not know each other.

53. Please press the “on” s______________.

52. What an e_________________ idea! Nobody else has thought of it.

51. Your dress is not of the right l_______________; it is too short.