Answer:
I save lives on the ground and in the air
I am merry creature in pleasant time of year as in but certain seasons I sing that you can hear; And yet I'm made a by-word A very perfect mock; Compared to foolish persons And silliest of all folk.
What force and strength cannot get through, I with my unique teeth can do. What am I?
I am the type of room you cannot enter or leave. Raise from the ground below I could be poisonous or a delicious treat.
I am a nut with a hole
When I'm born I fly. When I'm alive I lay. When I'm dead I run.