Why do some questions not start with an auxiliary verb?

Question

When I learned English, my teachers told me that all questions **must** have an auxiliary verb at the beginning, just like *Are you mad?* or *Is she playing?* do. But when watching some movies or talking with people who speak English, they just ask using things like *You mad?* and *She’s playing?* Of course, the kind of intonation let me know they are asking a question, but why this happen?

Answer 1

Okay, so, first thing, your teacher wasn't wrong. It sounds better in a formal situation to use the article. That is why your teacher informed you that you 'must' use it. They wanted you to sound correct and educated.

However, remember that with English there are typically exceptions to rules unlike other languages.

What you are referring to is related to slang or street language. Typically, in slang, words are shortened or not even used at all. For example, "Y'all" comes from "You all", drop the 'ou'.

So, it sounds like the movies you are watching are likely have scenes with characters in less-than-formal conditions.

Hope this helps. ~W

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