‘Who’ll hear us say our prayers?’ asked Billy anxiously.
‘Whom you like.’
‘Won’t you?’
‘Yes, I will.’
‘Ursula?’
‘Well Billy?’
‘Is it WHOM you like?’
‘That’s it.’
‘Well what is WHOM?’
‘It’s the accusative of who.’
There was a moment’s contemplative silence, then the confiding:
‘Is