some lyric from a children's song written by Dr. Seuss
Hi, while watching episode 7 of the big bang theory, season 5, of course.
I came across some lyrics that I couldn't understand.

Leonard(one character) was asking Sheldon(another) whether he should go out with a certain woman while he already has his girlfriend.
Sheldon said "Dr. Seuss's song 'one fish, two fish, red fish, blue fish' might be able to help Leonard here"

I'm not sure as why?
Thanks so much

Question

some lyric from a children's song written by Dr. Seuss
Hi, while watching episode 7 of  the big bang theory, season 5, of course.
I came across some lyrics that I couldn't understand.

Leonard(one character) was asking Sheldon(another) whether he should go out with a certain woman while he already has his girlfriend.
Sheldon said "Dr. Seuss's song 'one fish, two fish, red fish, blue fish'  might be able to help Leonard here"

I'm not sure as why?
Thanks so much

Answer

Sheldon is saying that are many women for Leonard to choose from just like the Dr Seuss song:
One fish, two fish, red fish, blue fish.
 Black fish, blue fish, old fish, new fish.
 This one has a little star. 
This one has a little car. 
Say! What a lot of fish there are. 
Yes. Some are red.
 And some are blue.
 Some are old. 
And some are new. 
Some are sad.
 And some are glad. 
And some are very, very bad. 
Why are they sad and glad and bad?
 I do not know. 
Go ask your dad.
 Some are thin. 
And some are fat
 The fat one has a yellow hat. 
From there to here, from here to there, funny things are everywhere.

Answer

a children's song ? 好好学习一下's的用法。

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