See but not hear:
If there is a glass partition that is thick;
If you are wearing noise-cancellation headphones or ear plugs;
If you have a significant hearing impairment.
Hear but not see:
If your eyes are closed it you have a significant visual impairment;
If you are facing away from a person;
If there is a wall or other obstruction between you.
See but not hear. You can see them but not hear them when they are in a forest where a tree is falling on them, so nobody is left there to tell if either the tree or the person hit by it make a sound.
You can see someone taking off in a plane or a train, but you can’t hear him.
From the audience, you can hear someone singing from back stage.
You can hear your baby crying, but may not be able to see him in his crib 2 rooms away.
You may see someone under water, but not hear them call you. I hope you could see him waving for help.
@KaY_Jelly It just occurred to me that I can’t hear you OR see you, but I know exactly what you said and have a clear picture of your looks—nothing like those of Stuart Little.