177. in the field, on the field

　in the field在野外，on the field在战场上 He lost his life on the field.

176. in the air, on the air, in the sky

　in the air正在酝酿中，on the air播送，广播，in the sky在天空中 His show is on the air at 6:00 tonight.

175. in surprise, to one's surprise, by surprise

　in surprise惊奇地，to one's surprise使某人吃惊的是，by surprise使…惊慌 The question took the professor by surprise.

174. on earth, on the earth, in the earth

　on earth在世上，在人间，到底，究竟，一点也不，on the earth在地上，在地球上，in the earth在地下，在泥土里 no use on earth

173. at peace, in peace

　at peace平静地，in peace和平地 live in peace with one's neighbors

172. warn sb. of, warn sb. against

　warn sb. of提醒某人注意某事，warn sb. against提醒某人不要做某事 warm him against swimming in that part of the river

171. on the corner, in the corner, at the corner

　on the corner物体表面的角上，in the corner物体内部的角落里，at the corner物体外部的角落上(拐角处)on the corner of the table

170. since, for (完成时间状语)

　since接点时间或一句话，for接一段时间 for three years, since 3:00

169. after, behind (表位置)

　after强调次序的先后，behind强调物体静态位置的前后 There are many trees behind the house.

168. between, among

　between两者之间，三者或三者以上两两之间, among三者或三者以上之间

　Switzerland lies between France, Germany, Australia and Italy.