He took a deep breath and let it out in a sigh.

After a moment she let out her breath in a sigh.

After a moment he let out his breath in a long sigh.

I took another deep breath; let it out in a sigh.

He turned back to the board and drew a deep breath, then let it out in a sigh.

He let out his own breath in a sigh of relief.

I closed my eyes and let the air out in a long slow sigh.

She let it out in a long, quiet sigh of relief.

I let my breath out in a long, slow sigh.

She drew breath to tell him not to say such a thing, then let it out in a sigh.