Well, "slithy" means "lithe and slimy." "Lithe" is the same as "active." You see it's like a portmanteau - there are two meanings packed up into one word.
It is a very inconvenient habit of kittens (Alice had once made the remark) that, whatever you say to them, they always purr: "If they would only purr for 'yes,' and mew for 'no,; or any rule of that sort," she had said, "so that one could keep up a conversation! But how can you talk with a person if they always say the same thing?
While the laughter of joy is in full harmony with our deeper life, the laughter of amusement should be kept apart from it. The danger is too great of thus learning to look at solemn things in a spirit of mockery, and to seek in them opportunities for exercising wit.
Be what you would seem to be - or, if you'd like it put more simply - never imagine yourself not to be otherwise than what it might appear to others that what you were or might have been was not otherwise than what you had been would have appeared to them to be otherwise.
Crawling at your feet,' said the Gnat (Alice drew her feet back in some alarm), `you may observe a Bread-and-Butterfly. Its wings are thin slices of Bread-and-butter, its body is a crust, and its head is a lump of sugar.' And what does IT live on?' Weak tea with cream in it.' A new difficulty came into Alice's head. `Supposing it couldn't find any?' she suggested. Then it would die, of course.' But that must happen very often,' Alice remarked thoughtfully. It always happens,' said the Gnat.
Alice laughed. 'There's no use trying,' she said. 'One can't believe impossible things.' I daresay you haven't had much practice,' said the Queen. 'When I was your age, I always did it for half-an-hour a day. Why, sometimes I've believed as many as six impossible things before breakfast. There goes the shawl again!
I confess I do not admire naked boys. They always seem to me to need clothes, whereas one hardly sees why the lovely forms of girls should ever be covered up.
"In my youth," said his father, "I look to the law, And argued each case with my wife; And the muscular strength, which it gave to my jaw Has lasted the rest of my life."