We normally use "since" to mean "from a time in the past until a later past time, or until now".
Can we use "since" in future tenses, for example, "I will be free since 6pm today. Now is 3pm"?
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Sign up to join this communityWe normally use "since" to mean "from a time in the past until a later past time, or until now".
Can we use "since" in future tenses, for example, "I will be free since 6pm today. Now is 3pm"?
Yes we can use "since" with some future tenses, but "will" is not one of them. Future perfect, however, is:
I will have been free since 6 pm.
Though this isn't the most natural way to phrase the idea, the grammar is good. A more natural context would be one where the duration is being emphasized, not the starting point:
A: Let's go dancing after I finish work tomorrow.
B: No thanks. I'll have been on my feet since 9 am, so the last thing I'll want to do is dance.