Almost all of these are wrong.

Which of these sentences is correct?

1. Almost Japanese make this mistake.
2. Almost these sentences are wrong.
3. Almost people forget that "almost" is an adverb.
4. I hear this mistake almost every day.
5. This word is almost used correctly.
   

While the meaning of all of these sentences is true, the only one which is grammatically correct is number 4. Please remember that "almost" is an adverb. That means it can modify another adverb or an adjective, but it cannot be used to directly modify a noun. Here are the correct versions:

1. Almost all Japanese make this mistake.
2. Almost all of these sentences are wrong.
3. Almost all people forget that "almost" is an adverb.
4. I hear this mistake almost every day.
5. This word is almost never used correctly.