In this video, learn the difference between "leave" and "left" and improve your basic English grammar. The verb "to leave" is a very common verb in English. It's used in many different expressions as well. To feel confident using this verb, you need to understand its sentence structure. "Leave" is the base form of the verb "to leave". The base verb is used in the present simple and the imperative. In the present simple, you also have to conjugate the verb according to the subject, and add as "s"