"Are you tired? Your face looks like a tribble."

Translation: bIDoy''a'? yIH rur qablIj.

[rockhyrax]

What's Klingonese for shade?!

[jdmcowan]

Since this is a type of classroom, and you asked (though I recognize that it was probably more rhetorical than serious), Klingons probably would not use "shade" with that idiomatic meaning. "Shadow" is QIb and "to insult" is tIch.

[rockhyrax]

Although my question was not "serious", I appreciate the answer!
OK, I'm going out on a limb here, so might an answer to the question (are you tired, your face looks like a tribble) be the following (presuming there's a Klingon subculture that would use such idiom)?
QIbmoHbogh vum SoH
My reasoning: "throwing shade" is sort of a synonym for causing shadow, so "you're a shady b..." would be "you're a jerk who causes shadow to exist". (I haven't got as far in the course as talking about casting a shadow on someone or something.)

[jdmcowan]

QIb is only a noun and definitely cannot take verb suffixes like -moH and -bogh.

We don't actually know the ideal way to talk about casting a shadow and we have to be creative in talking about such. One possible way is to use chen: QIb chenmoH ghaH "He causes a shadow to form."

I have serious doubts that there is a Klingon subculture that would use the idiom you suggest, but if we were talking about casting actual shadows, I would probably say QIb chenmoHbogh vum SoH "You are a jerk who causes shadow to form." Of course it's not much of a put down since we all cast shadows.