5 + subjun
como vengas tarde, no comes if you're late you'll get nothing to eat
como sea cierto, ¡estamos perdidos! if it's true, we're done for!
¡como lo pierdas! you'd better not lose it!, don't you lose it!
→ como no
como no lo haga en seguida ... if he doesn't do it at once ..., unless he does it at once ...
no salimos, como no sea para ir al cine we only go out if it's to go to the cinema, we don't go out unless it's to go to the cinema