For most past simple questions, use did before the subject and the base verb after it. For a negative, use did not or didn't before the base verb. Say Did he leave? and He didn't leave, not Did he left? or He didn't left.
Use the present simple for what usually happens or is generally true. Use am, is, or are plus a verb ending in -ing for what is happening now or for a temporary situation.
Use do with I, you, we, and they. Use does with he, she, it, and one person or thing. After do or does, use the base verb: Does Maya work here? Yes, she does.
Use hear when you notice or receive a sound. Use listen when you pay attention, usually with to before the person, sound, or thing you are listening to.
Choose a short regular study time, work on one clear task, use English in more than one way, and review a few useful words or sentences later in the week.
Use not with a helping verb: do not work, is not late, cannot come, and did not call. After do not, does not, and did not, use the base form of the main verb.
Use a reflexive pronoun when the subject and object are the same. Match the subject: I becomes myself, you becomes yourself or yourselves, and they becomes themselves.
Use a possessive determiner before a noun: my bag, her plan, or their office. Match the word to the owner or group, and do not add an apostrophe to these forms.
Choose the preposition from the relationship you can see. Use in for an enclosed space, on for a surface, at for a point or meeting place, under for a lower position, and between or next to for positions in relation to other things.
Use at with a precise point, on with a day or date, and in with a larger period. Use since to name when a situation began, and by to name the latest acceptable time.