1. I don't have any special plans for this weekend.

2. I don't have any special plans during this weekend.
3. I don't have any special plans on this weekend.
4. I don't have any special pans this weekend.
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Which ones are correct? I think #3 is incorrect, for we should not put 'on' before 'this winter', 'this month', 'this weekend', etc. Am I right?

What about #1 and #2? Can we use both?

Is 'for this weekend' used as an adjective phrase or an adverb phrase in Sentence 1?

In #4, this weekend is an adverb phrase. What is the difference between #1 and #4?

Yes, #3 Is Incorrect. But what do you think is correct?

I think the rest are all correct.

1. I don't have any special plans for this weekend.

This one is commonly used, isn't it?
Is 'for this weekend' an adjective phrase, modifying 'any special plans'?
What is the meaning of 'for' in this sentence?

We've been through this before. Where is "for this weekend" in the sentence? After what word? What does that tell you?

And you should have looked up "for" in the dictionary website I gave you yesterday.

Out of the given sentences, #1 and #4 are correct, while #2 and #3 are grammatically incorrect.

Regarding #2 and #3, you are correct. We do not typically use the preposition "on" before time expressions like "this weekend," "this winter," or "this month."

Sentence #1 ("I don't have any special plans for this weekend") and sentence #4 ("I don't have any special plans this weekend") are both correct, but they have slightly different meanings and structures.

In sentence #1, "for this weekend" is used as a prepositional phrase. The preposition "for" shows the reason or purpose of not having any special plans. Therefore, it functions as an adverbial phrase modifying the verb "have." It answers the question "Why don't I have any special plans?" by indicating "for this weekend."

In sentence #4, "this weekend" is used as an adverbial phrase, modifying the verb "have." It answers the question "When don't I have any special plans?" by specifying "this weekend."

To summarize, the difference between #1 and #4 lies in the function of the phrases. In #1, "for this weekend" explains the reason, whereas in #4, "this weekend" specifies the time.