Interesting aside on punctuation: since Chinese is a tonal language, you can't turn a statement into a question by raising your tone at the end, because that just makes it a different sentence. So the use of a question word is required. For basic affirmative/negative questions, Mandarin takes a statement and ads 吗 "ma" to the end. Other types of questions have different words, though we have those in English too (where, when, how many, etc.)
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