competition 多指体育运动中的各项比赛、角逐，也指知识、技巧等方面的竞赛。
contest 多指在音乐、书法、演讲等方面所进行的比赛或竞争。其结果，由评判委员会裁决。
match 通常指体育运动项目的比赛，隐含势均力敌意味。
参考例句
1. But there is some pretty stiff competition. 但是还是有相当激烈的竞争。
2. They do not like competition or bureaucracy. 他们不喜欢竞争或官僚作风。
3. This competition is open to all, anyone in the whole world can participate! ! 这次比赛是向所有人开放，任何人在整个世界可以参加！
英英解释
n.
1. a business relation in which two parties compete to gain customers
2. an occasion on which a winner is selected from among two or more contestants
3. the act of competing as for profit or a prize
4. the contestant you hope to defeat
