[al:新概念英语（二）] [ar:MP3 同步字幕版（英音）] [ti:By Air] [by:更多学习内容，请到chazidian.com搜索“新概念”] [00:12.30]Why did the plane turn back? [00:17.49]I used to travel by air a great deal when I was a boy. [00:22.16]My parents used to live in South America and I used to fly there from Europe in the holidays. [00:30.07]A flight attendant would take charge of me and I never had an unpleasant experience. [00:36.65]I am used to travelling by air and only on one occasion have I ever felt frightened. [00:44.07]After taking off, we were flying low over the city and slowly gaining height, [00:51.06]when the plane suddenly turned round and flew back to the airport. [00:56.51]While we were waiting to land, a flight attendant told us to keep calm [01:01.80]and to get off the plane quietly as soon as it had touched down. [01:07.30]Everybody on board was worried and we were curious to find out what had happened. [01:14.08]Later we learnt that there was a very important person on board. [01:19.96]The police had been told that a bomb had been planted on the plane. [01:24.87]After we had landed, the plane was searched thoroughly. [01:29.91]Fortunately, nothing was found and five hours later we were able to take off again.