Languages › English as a Second Language Know your Auxiliary Verbs Share Flipboard Email Print English as a Second Language Grammar Pronunciation & Conversation Vocabulary Writing Skills Reading Comprehension Business English Resources for Teachers By Kenneth Beare English as a Second Language (ESL) Expert TESOL Diploma, Trinity College London M.A., Music Performance, Cologne University of Music B.A., Vocal Performance, Eastman School of Music Kenneth Beare is an English as a Second Language (ESL) teacher and course developer with over three decades of teaching experience. our editorial process Kenneth Beare Updated April 02, 2017 Auxiliary verbs are conjugated depending on the subject of a sentence. Here are a few examples of auxiliary verbs: Tom has lived in Boston for twenty years.They didn't come to the party last night.I was cooking dinner when you telephoned.What are you doing tomorrow afternoon? Knowing correct auxiliary verb usage is key to tense usage. Every tense takes an auxiliary form of the verb. There are three exceptions to this rule: Simple present positive: She works at a bank.Simple past positive: He bought a new TV last week.Positive imperative statements: Hurry up! There are also a number of short forms that take ONLY the auxiliary form of the verb: Yes / No answer short forms: Do you live in England? - No, I don't.Has she been to Paris? - Yes, she has. Question tags: They enjoy learning English, don't they?He won't agree with me, will he? Positive agreement / inclusion: I went to the beach last weekend. - So did I.I'm working very hard at the moment. - So is she. Negative agreement / inclusion: They haven't worked here long. - Neither have I.We won't be able to come next week. - Neither will I. Overview of Auxiliary Verb Usage DO / DOES Used simple present question and negative forms: What time does he get up?They don't drive to work. They take the bus. DID Used in simple past question and negative forms: When did they arrive yesterday?He didn't finish his homework last week. IS / ARE / AM Used in present continuous and for the future with 'going to': They are working hard at the moment.She is going to study medicine at university. WAS / WERE Past continuous: I was watching TV when you arrived.What were they doing while you were cooking dinner? HAVE / HAS Present perfect and present perfect continuous: How long have you lived here?I've been working since seven this morning. HAD Past perfect and past perfect continuous: He had eaten by the time I arrived.She had been studying for two hours when he finally telephoned. WILL / WON'T Future with 'will': What will the weather be like tomorrow?He won't understand. If you don't understand all of these tenses, don't worry. This overview chart shows the positive, negative and interrogative (question) forms of all the principal tenses in English with a brief description of the principal usage. The timeline tenses chart provides a handy visual reference sheet to English tenses and their relationship to the past, present and future. Included you will find active, passive, simple and continuous forms positioned according to their occurrence in time. Test your Understanding of Auxiliary Verbs In each of the following sentences, an auxiliary verb is missing. Write the missing auxiliary verbs on a piece of paper and then check the answers below. He _____ come to school yesterday because he was ill.She _____ been working in the garden since two this afternoon.He _____ finished his homework by the time arrived.I'm afraid I _____ be able to come to the party. I have to study.You've visited London, _____ you?They _____ going to attend a meeting in Chicago next week.Why _____ you buy that?! It's ugly!She _____ often go to the movies.He _____ watching TV. He's doing his homework at the moment.They _____ been playing tennis for two hours.I don't like country music. - Neither _____ I.They won't come to the party, _____ they?Mom _____ been working for two hours when I telephoned.I think they are fantastic! - So _____ she.What _____ they doing?Mary hasn't enjoyed herself so much for a long time. - Neither _____ I.Mike _____ go on vacation last summer. He was too busy.He's studying Russian this semester, _____ he?I _____ just been to the bank.How long _____ you been working for this company? Answers: Auxiliary Verb Quiz He didn't come to school yesterday because he was ill.She has been working in the garden since two this afternoon.He had finished his homework by the time arrived.I'm afraid I won't be able to come to the party. I have to study.You've visited London, haven't you?They're going to attend a meeting in Chicago next week.Why did you buy that?! It's ugly!She doesn't often go to the movies.He isn't watching TV. He's doing his homework at the moment.They've been playing tennis for two hours.I don't like country music. - Neither do I.They won't come to the party, will they?Mom had been working for two hours when I telephoned.I think they are fantastic! - So does she.What are they doing?Mary hasn't enjoyed herself so much for a long time. - Neither have I.Mike didn't go on vacation last summer. He was too busy.He's studying Russian this semester, isn't he?I've just been to the bank.How long have you been working for this company?