Remember, for is used with a period of time. Since is used to refer to a specific point in time. You can use for and since with similar verb tenses, if you wish.

When should we use to and for?

You need to use “to.” It might seem complicated, but the answer is actually very simple. Use “to” when the reason or purpose is a verb. Use “for” when the reason or purpose is a noun.

What we use since or for with morning?

Since is used with the present perfect tense to say when something began. It has been raining since morning. I have been waiting for his call since yesterday.