1. We are going to start/begin the class debate contest.

2. The school debate contest will be held soon.

3. Let's begin the school debate contest.
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Can a student use all the directions when he begins the debate as an MC? Do we have to use 'contest'? What about deleting 'contest'?

2 answers

1. We are going to start/begin the class debate contest.

2. The school debate contest will be held soon.

3. Let's begin the school debate contest.

4. We'll have the school debate contest.
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Can a student use all the directions when he begins the debate as an MC? Do we have to use 'contest'? What about deleting 'contest'?
You don't need to use the word "contest." The word "debate" is already a noun and serves the purpose.

Yes, delete "contest"!!