Learn Dutch: Werken deze mensen hier? - Do these people work here?

Dutch doesn't use helper words like "do" or "does" to ask questions. Instead, it just puts the main verb at the very front of the sentence. So instead of "Do these people work here?", Dutch literally says "Work these people here?".

This lesson is about question words. Why doesn't this sentence use one?

Because this is a "yes/no" question. When you want an open answer, you start with a question word like waarom (why) or wanneer (when). But when the answer is just yes or no, you simply start the sentence with the verb (werken).

Why is it deze mensen and not dit mensen?

Mensen (people) is plural. In Dutch, all plural nouns use the word deze (these) or die (those) to point at things, even if their singular form uses het and dit.

Is mensen the plural form of another word?

Yes, it is the plural of mens, which means "human" or "person". While English has two completely different words ("person" and "people"), Dutch just makes the word for "human" plural by adding -en.