“I'd love to, but I can't do Friday.”
A polite refusal first shows enthusiasm with I'd love to, explains the conflict after but, and offers an alternative with How about Saturday? Can't do Friday is a casual way to say Friday is unavailable.
B1-24 / CEFR B1 / EPISODE 24
Suggesting an alternative when plans clash
SceneTina is meeting Frank at their usual café after her first date with someone new.

WORDS & CONTEXT
A polite refusal first shows enthusiasm with I'd love to, explains the conflict after but, and offers an alternative with How about Saturday? Can't do Friday is a casual way to say Friday is unavailable.