feet on the ground
get one's feet on the ground
keep one's feet on the ground
have one's feet planted firmly in the ground
An understanding of what can be done; sensible ideas. Used with a possessive.
John has his feet on the ground; he knows he cannot learn everything at once.
Ted dreams of sudden riches, but Henry keeps his feet on the ground and expects to work for his money.
Mrs. Smith was a dreamer, but her husband was a man with his feet on the ground.