are unhappy.

16. All birds, that do not sing loud, are unhappy; No well-fed
birds fail to sing loud.

__________

Taking "persons" as Universe; m="in the house"; x="John";
and y="having a tooth-ache"; represent

17. John is in the house; Everybody in the house is suffering
from tooth-ache.

18. There is no one in the house but John; Nobody, out of
the house, has a tooth-ache.

__________

[See pp. 68-70]

Taking "persons" as Universe; m="I"; x="that has taken a
walk"; y="that feels better"; represent

19. I have been out for a walk; I feel much better.

__________

Choosing your own 'Universe' &c., represent

20. I sent him to bring me a kitten; He brought me a kettle