Answer:
I save lives on the ground and in the air
I have married many woman but has never been married
Where I am there is no south, west, nor east, and weather is not fit for man or beast. What am I?
I can be swallowed, but I can also swallow you. What am I?
I walk on 4 legs in the morning, 2 legs at noon, and 3 legs at night. What am I?
Whoever made me don't want me. Whoever bought me don't need me. Whoever use me don't know me.