1. However hard you may study, you can not get a good point.

2. However hard you may study, you can not get a good grade.

3. However hard you may study, you can not get good points on the exams.

4. However hard you may study, you can not get good grades on the exams.

5. However hard you study, you can not get good grades on the exams.
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Which ones are grammatically correct? Would you compare #4 and #5? Are both the same? Without 'may,' what is different in meaning?

"cannot" is spelled as one word usually.

1 and 3 seem odd, but 2, 4, and 5 are fine. It makes no difference whether "may" is included or omitted.

All the sentences you provided are grammatically correct and have similar structures. However, there are slight differences in meaning and emphasis. Let's analyze them one by one:

1. However hard you may study, you cannot get a good point. (singular)
2. However hard you may study, you cannot get a good grade. (singular)
3. However hard you may study, you cannot get good points on the exams. (plural)
4. However hard you may study, you cannot get good grades on the exams. (plural)
5. However hard you study, you cannot get good grades on the exams. (plural)

In sentences 1 and 2, the use of "point" and "grade" indicates that the speaker is talking about a single assessment or result. The singular forms suggest that the speaker is referring to a specific point or grade.

Sentences 3, 4, and 5, on the other hand, use the plural forms "points" and "grades," which suggest a broader scope. In these sentences, the speaker is emphasizing that no matter how hard one studies, it is not possible to achieve good results in multiple exams or assessments.

Comparing sentence 4 and 5, they are very similar in meaning. The only difference is the use of "However hard you may study" versus "However hard you study." The inclusion of "may" in sentence 4 adds a slight sense of possibility or uncertainty. It suggests that even if you study extremely hard or to the best of your abilities, it is still unlikely to achieve good grades. Sentence 5, on the other hand, states the same idea without the inclusion of "may," giving a more definitive statement.

In summary, both sentence 4 and 5 convey the same message about the difficulty of achieving good grades through studying, but sentence 4 includes a slight element of uncertainty or possibility.