Step-by-step explanation:
It is true that the wings of the bee move very fast. The wings are smaller than their body and it is believed to be difficult for the wings to lift the whole body of the bee.
Sometimes, bees carry nectar and pollen with itself which again increases their weight. It has been found that the wings do not move up and down rather moves to and from. Since air is denser, it tries to push the air downwards and lift itself upwards.