Generate the answer for a given question. The question requires common knowledge of English. Make sure that the answer is in detail, long, consistent with the context, and requires general knowledge of English. To be less repetitive, please vary your language for each question. Give a proper explanation to answer, and if necessary, provide the definition of various terms. And conclude your answer if it's long. If you have used other resources (e.g., Merriam Webster's.) to answer the question, include citations in your answer. You don't need to paraphrase the context of your resources, but make sure that your answer is consistent and complete.

Q: Is there a name for these kind of doubled words? For example: hanky-panky flim-flam hoity-toity boo-hoo zig-zag Note that some rhyme and others do not.

A: hanky-panky is an example of rhyming reduplication zig-zag is an example of ablaut reduplication.
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Q: The US emergency telephone number 911 seems to be almost always pronounced as nine one one whereas the Porsche model is typically pronounced as nine eleven One reason I can think of for preferring 'nine one one' for the phone number is that there is no 'eleven' key on a phone. On the other hand, '0800' is often pronounced 'o eight hundred'. Is there a logical or historical reason for the different pronunciations?.

A: How a car manufacturer names its models is more of a marketing preference than anything, but in general you'll find that the Porche model is the norm. Ask any schoolchild to read aloud the number '911' and you'll get 'nine hundred and eleven', not 'nine one one'. The telephone number 9-1-1 was, as you speculated, spelled out specifically to prevent people - particularly children - from getting confused looking for the 'eleven' key on the telephone. I have heard this anecdotally countless times, but I'm having a hard time finding an authoritative source. Closest I can come are various 'history of 911' websites like this one: Dr. Phil Shaenman, head of the U.S. Fire Administration's research department, authored a paper explaining that children should be taught to dial 'nine-one-one,' and not 'nine-eleven.' He pointed out that a child's conceptual abilities prevent them from recognizing the difference between '11' and '1-1.'
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Q: I've found that expression on a website, and I don't understand it. At first I thought it was because the canary is yellow and the coal black... but it doesn't make much sense.

A:
A canary in a coal mine is an advanced warning of some danger. The metaphor originates from the times when miners used to carry caged canaries while at work; if there was any methane or carbon monoxide in the mine, the canary would die before the levels of the gas reached those hazardous to humans. See here.
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