What's the smallest bird in the word Hummingbirds are the sm

What's the smallest bird in the word Hummingbirds are the smallest birds in the world.One kind of
hummingbird is only two inches long.lt is also as light as a penny
A hummingbird is very fast.It can fly straight up and down.It can even fIy backwards
The wings of a hummingbird move very quickly.You can't see them move.But you can hear them.The wings make a humming sound.That is why we call the little bird a hummingbird.
1.A hummingbird is only **** ****long
2.We can only **** the wings sound but can't **** ****them move.
3.It can fly straight up and ******and also can fly