The window is open.

The window is open.

An open syllable ends with a vowel.

The open fracture requires immediate surgical intervention.

I wrote an open letter to the mayor to express my concerns.

Ask an open-ended question to encourage discussion.

The door was wide open.

She likes to keep open house for her friends.

They have always had an open house for their friends.

He's stating the obvious by insisting on this point.