Frost warning - which veggies to cover?

I know broccoli and cabbage and peas don't mind cold temps, but what about frost? Should they be covered?

I covered tomatoes and (if my husband could find it) my one pepper plant.

OK, just read the advisory again... not expecting a hard freeze and only a concern for "sensitive plants". The hourly temp forecast says it may get down to 31. I don't think the broccoli, cabbage, and peas will care too much.... hopefully.