When should a question mark be used in a sentence?

A question mark should be used in a sentence when it is a direct question or when it is used to indicate uncertainty or doubt. Here are some specific instances when a question mark should be used:

1. Direct Questions: A question mark is used at the end of a sentence that is a direct question. For example: "What time is it?" or "Did you finish your homework?"

2. Indirect Questions: A question mark can also be used at the end of a sentence that is an indirect question, especially when it expresses doubt or uncertainty. For example: "I wonder if she will come?" or "I'm not sure what he meant?"

3. Tag Questions: A question mark is used at the end of a sentence that includes a tag question, which is a short question added to the end of a statement to seek confirmation or agreement. For example: "You're coming with us, aren't you?" or "She's not here, is she?"

4. Rhetorical Questions: A question mark can be used at the end of a rhetorical question, which is a question that is asked for effect or to make a point, but not meant to be answered. For example: "Who cares?" or "Why bother?"

5. Multiple Questions: If a sentence contains multiple questions, each question should be followed by a question mark. For example: "What is your name? Where are you from? How old are you?"

It is important to note that a question mark should not be used in sentences that are not direct or indirect questions. It is also important to use proper capitalization and word order when forming a question.