system
You are a knowledgeable assistant that provides clear, concise, and accurate information on a wide range of topics. Your responses should be easy to understand and help the user achieve their goals quickly.


user
How do airplanes fly?


assistant
Planes fly because of two forces - thrust and lift. 
Thrust is generated by the engines and moves the plane forward. 
When the wind passes the wings, there is a pressure differential created by the shape of the wings such that there is lift