air, heir

Air or air means the stuff that we breathe, that you can't see except for its action as wind--
He let the air out of all the balloons when the party was over.
Open the window and let in some air.

Heir or heir ( rhymes with air ) means the person who inherits an estate or kingdom--
His son was his only surviving heir, and inherited everything.
It was important to the king that he leave an heir to the throne.

Now that you know that, you can say--
"Though the air was thick with smoke, the guard rushed in to rescue his employer's  heir."

Note--an "heiress" is a female who inherits, or who will inherit, an estate--
The fortune hunter had designs on the young heiress.
"Airless" means close and stifling, without air--
They found it difficult to breathe in the airless room.
"Hairless" means bald--
This dog is a Mexican hairless.
Note # 2--"air" may be used to mean an aspect of demeanor--
He had the air of a failed poet.
To "put on airs" means to pretend to something grander than we are--
The swineherd's daughter often put on airs, and pretended to be a great lady.
Note # 3-- "air" and "heir" are not to be confused with "hair" , meaning the stuff that grows on human heads, or "hare", a kind of a rabbit.
Note # 4--"ere" ( rhymes with air ) is an old-fashioned or poetic way of saying "before" ( in time )--
"Able was I ere I saw Elba."
Not to be confused with  "err" ( rhymes with "her"  ), meaning to make a mistake--
"To err is human, to forgive, divine."
Note# 5--"eyre" ( rhymes with air ) means a journey in a circuit, as some judges once made--
An old English justice in eyre examined county records and held court.