音频中提到的单词，音标和例句

cycle /ˈsaɪkl/   (n.) bicycle, motorcycle （v）ride a bicycle

bicycle  /ˈbaɪsɪkl/ 自行车

tricycle /ˈtraɪsɪkl/ 三轮车

motorcycle /ˈməʊtəsaɪkl/ 摩托车

I usually go to school by cycle. 我通常骑车上课

I usually go to school by bike.

I usually cycle to school.

I often do 4 min cycling in the evening.   我常在傍晚骑四分钟自行车作为锻炼。

Cycling is good to my health. 骑自行车锻炼有益于健康

cycle of seasons 季节的轮替， 

life cycle生命周期