>It's easier said than done. Can you fake being able to run like Usain Bolt?
Fortunately, parent didn't advice to fake running like Bolt, just to fake something everybody (except a tiny minority with actual clinical issues) can do: feign interest.
True, I am exaggerating a little to get the point across, but the point stays - it's harder for some people that others, and that's not that easily controllable.
Fortunately, parent didn't advice to fake running like Bolt, just to fake something everybody (except a tiny minority with actual clinical issues) can do: feign interest.