Some time (grammar)

1.    Some time is a combination of a noun (time) and determiner (some). It shows an unspecified amount of time (in the same way we say: some money or some work). For example:

It will take us some time to finish this project. (it’s unknown how much time it will take to complete the project)

Sometime is an adverb that means approximately. Although the exact time is still unspecified, this word is used with other adverbials (next week/this year) giving listeners an idea of a time frame:

He said he’d come sometime after lunch. (we’re unsure when exactly he’ll come, but we know it’ll be after lunch hour)

Sometimes is an adverb that means occasionally.

I usually drive to work, but sometimes I take a bus.

 Sometime means "at an indefinite or unstated time in the future." Some time means "a period of time." Sometimes means "occasionally, now and then."

Examples:

"Why don't you come up sometime and see me?"
(Mae West in She Done Him Wrong, 1933)

"You must give some time to your fellow men. Even if it's a little thing, do something for others--something for which you get no pay but the privilege of doing it."
(Albert Schweitzer)

"I am so clever that sometimes I don't understand a single word of what I am saying."
(Oscar Wilde)