They mean different things. See examples and get the spelling right.
Want to hate English while feeling dark and moody? Note that these mean different things:
As I'm writing this tip I have the Depeche Mode song "Sometimes" in my head.
"Sometimes" means "now and then" or "occasionally," so when they wrote the lyrics "Sometimes I question everything," they used it properly. Thank goodness! I'd hate my college memories to be tainted by a love of bad usage.
"Sometime" means "at some unspecified time": Let's get dinner and reminisce over Depeche Mode sometime.
"Some time" means "quite a while": I think I'll spend some time listening to that old Depeche Mode tape again.
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