Modals are a type of auxiliary verb that express various meanings such as ability, permission, obligation, possibility, and necessity. They are used to modify the meaning of the main verb in a sentence. The most common modals in English are can, could, may, might, must, shall, should, will, and would.

Examples:

• I can speak Spanish fluently. (ability)
• Could you please pass me the salt? (polite request)
• You must finish your homework before you can watch TV. (obligation)
• It may rain later, so bring an umbrella. (possibility)
• We should arrive at the airport early to avoid missing our flight. (advice)
• Will you be attending the meeting tomorrow? (future action)
• If I had more time, I would travel the world. (hypothetical situation)