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All the students have to participate in the conference.
All students have to participate in the conference.

---> is there any difference in meaning between "all the students" and "all students"?
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'The' refers to some specific students in the context; however, in most cases, 'all' is by nature inclusive, so that either form works.
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THey both mean the same thing, they are both correct.

All student is more general than All the students.
thank you for your reply!
I have one more question.
Could the word- "ALL" modify sg. noun form? For example.... "all student" and " all the student" ??
Not likely. 'All the sugar'; 'All belief'. But I suppose 'all the cow is edible' is possible.
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All students sits in class when the bell rung in school. My question all students or all student

Thank u

All the students were (sitting) in class when the school bell rang.

CJ

Thanks for helping out

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