1. They made a mistake.

2. They made two mistakes in composition.

3. They made few misatakes in writing.

4. They made some mistakes because they didn't know how to solve the problems.

5. Don't be afraid of making mistakes when you speak English. Be bold and speak English in a loud voice. Then you will become good speakers in the future.
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Are the sentences all grammatical? Would you correct errors, if any? Thank you.

The only error I see is the spelling of "mistakes" in #3. Everything else is fine.

1. The sentence is grammatically correct.

2. The sentence is grammatically correct.

3. There is a spelling error in the word "misatakes." The correct spelling is "mistakes." The corrected sentence would be: "They made a few mistakes in writing."

4. The sentence is grammatically correct.

5. There are a few errors in the sentence. Here's the corrected version: "Don't be afraid of making mistakes when you speak English. Be bold and speak English in a loud voice. This way, you will become a good speaker in the future."