Written ‘gh’ has no sound of its own.
It’s never pronounced as it’s written, i.e. /gh/.
Sometimes written ‘gh’ is even pronounced /f, g, p/.
cough … trough … ought to … wrought
/kɔf/ … /trɔf/ … /ˈɔ-də/ … /rɔt/
cough … coughing
/kɔf/ … /ˈkɔ--fɪŋ/
The girl has a bad cough.
She can’t stop coughing.
She ought to get some cough medicine.
The horse is drinking from a watering trough.
A business cycle has a peak and a trough.
There ought to be a better way.
You look awful. You ought to go back to bed.
A blacksmith works with wrought iron.
“Wrought” is an archaic form of the verb “to work,”
so “wrought iron” means “worked iron.”
What a spectacular wrought iron gate!