some time / sometime / sometimes
A span, an unspecified time, and now and then.
Some time is a span: some time to think. Sometime is an unspecified time, or former: sometime next week; a sometime clerk. Sometimes means now and then.
Examples
UseWe need some time to read it.
UseCall sometime after noon.
UseThe gate sometimes sticks.
AvoidWe need sometime to read it.