61. be worried/serious about 为……而担心
62. because of=thanks to 由于
63. be afraid/terrified to+v/ of+v-ing 对...害怕。
64. break into "闯入, 破门而入"
65. by air mail 寄航空邮件
66. by bus 乘公共汽车
67. by oneself 亲自
68. by phone 打电话
69. by the way 顺便说;顺便问一下
70. be strick with +sb/in +sth 对谁/某事严格.
71. call on 拜访 care for 照顾; 喜欢
72. carry out 执行
73. catch (a) cold 着凉;伤风
74. change one's mind 改变主意
75. check in 办理登机
76. come across 被理解; 遇见
77. come from 出生于;来自
78. come on 快;走吧;跟我来
79. come to an end 结束
80. come to know 知道