I wouldn't use #3, but #1 and #2 are opposites (or negatives) of each other.
#3 is not used, and #4 is VERY wordy. Since it's a "sometimes" idea, all you need is one half of that sentence or the other, but not both. Also, the word "sometimes" needs to be at the beginning of the sentence, not between the subject and verb.
#5 is well phrased. This is a really good opposite for #1.
1. I go to bed early on Saturdays.
2. I don't go to bed early on Saturdays.
3. I don't go to bed early every Saturday.
4. I sometimes go to bed on Saturday, and I sometimes don't go to bed on Saturday.
5. On Saturday, I never go to bed early.
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Are #2 and #3 the negative sentences of #1?
Does #3 mean #4? Does #2 mean #4?
Does #3 mean #5? Does #2 mean #5?
What is the exact meaning of #2 or #3 in negative sentences?
2 answers
#5 is correct