Answer:
What ship has no captain but two mates?
There are four of these, but everyone's favorite seems to be spades.
What word becomes smaller when you add 2 letters to it?
What has thousands of ribs and two backbones?
What 4-letter word can be written forward, backward or upside down, and can still be read from left to right?
I am a room that has a roof but no walls. What am I?