how to speak 參加 in English? (特別是比賽和活動)

你可以用 take part in, participate in, enter (for), be a part of, sign up for, join 等等。但若是比賽，就應避免用 join 。其實還有很多不同的字可以帶出「參加」的意思，請看以下例句：

I want to ___ the contest.
可用的字有 take part in, participate in, enter, sign up for, compete in, perform in, ...

I want to ___ the Carnival.
take part in, participate in, join, attend, go to, ...

I want to ___ the basketball team.
join, be a part of, become member of, ...

請參考我對你的另一問題的回答： http://hk.knowledge.yahoo.com/question/?qid=7007081202732

you can use "take part in" or "participate in"

e.g. I take part in a composition competition.