Sometimes they are more than sufficient.

Good-night.

Sleep well and don't dream, if you can help it." "And don't _you_ dream, Dad, especially about that wretched proposition.
Just have another pipe, and drink your whisky and go to bed.

There's something in your eyes that says you want a long night's rest.
Good-night now, and sleep well." She pulled his head down and kissed him twice on his grey, thin cheek, and then, with a wave of her hand and a laughing nod towards the Mummy, vanished through the closing study door to go and dream her dreams, which were not very likely to be of mummies and fourth dimensional problems, and left her father to dream his.
Then a couple of lines from one of "B.V.'s" poems, which had been running in his head all the evening, came back to him, and he murmured half-unconsciously: "'Was it hundreds of years ago, my love, Was it thousands of miles away... ?'" "And why should it not be?
Why should you, who were once Ma-Rim[=o]n, priest of Amen-Ra, in the City of Memphis--you who almost stood upon the threshold of the Inmost Sanctuary of Knowledge: you who, if your footsteps had not turned aside into the way of temptation and trodden the black path of Sin, might even now be dwelling on the Shores of Everlasting Peace in the Land of Amenti--dost _thou_ dare to ask such a question ?" The sudden change of the pronoun seemed to him to put the Clock of Time back indefinitely.
He was standing by his desk still facing the Mummy just as his daughter had left him after saying "good-night." He was not a man to be easily astonished.

Not only was he one of the best-read amateur Egyptologists in Europe, but he was also an ex-President of the Royal Society, a Member of the Psychical Research Society, and, moreover, Chairman of a recently appointed Commission on Comparative Insanity, the object of whose labours was to determine, if possible, what proportion of people outside asylums were mad or sane according to a standard which, somehow, no one had thought of inventing before--the standard of common-sense.
The voice, strangely like his daughter's and his dead wife's also, appeared to come from nowhere and yet from everywhere, and it had a faint and far-away echo in it which harmonised most marvellously with other echoes which seemed to come up out of the depths of his own soul.
Where had he heard it before?
Somewhere, certainly.