Lemonade.
or
Three skunks fighting over a pickle
First dog: My master calls me Furball. How about you?
Second Dog: My master calls me Sitboy
or
Rootbeer.
or
When it's ajar!
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First he lies on one side, then he lies on the other.
or
Only one, but she/he'll have to go out and buy the light bulb adaptor card first, which is extra.
or