2. Atmospheric pressure is very high, and a standard atmospheric pressure can support 10.3m water column; Because there is no air in the glass, that is to say, there is no air pressure inside, and the external air pressure is greater than the pressure of water in the glass on the cardboard, so the cardboard will naturally not fall.

3. Similar things are often reflected in our daily life, such as a clothes hanger stuck on a smooth wall (the air inside is squeezed and clings to the wall).

Similarities between animals and plants:

1. Everyone has basic living needs;

2. Both can grow and die;

3. Can breed offspring;

4. Everyone has a corresponding body structure;

Everyone can cope with external changes.

The main differences are:

1. The plant cannot change its position. It has only roots and no moving organs.

Food comes from different sources. Plants make their own nutrients in the body, so they don't need mouths and teeth.