Transcript Modal verbs
Modal verbs Forms of Modals Modals do not take third person -s √ The nurse can give the injection. x The nurse cans give the injection. The infinitive is used after the modal verb. √ The planes must take off now. √ The wastage can be stopped. √ The technical glitch could have been avoided. x She should recycles that paper. eg1471/jc/dec2008 Forms of Modals In negative sentences, not follows the modal even when be or have are present. The investigation may not end today. √ The survey should not have yielded such results. √ The lecturer could not be there at this hour. √ The lecturer could be not there at this hour. x Do not use the contracted forms of negatives in formal writing. Use cannot and not can’t . eg1471/jc/dec2008 Uses of Modals To express: ability degrees of possibility advisability necessity eg1471/jc/dec2008 Modals Expressing Ability Modals Meaning Can Express (a lack of) The new employee can drive. physical ability or skill The astronaut cannot go up the space shuttle today. Could Express a (lack of) past ability or skill In the 1800s, people could not communicate with each other across the globe via email. Could have + past participle Refers to a past situation in which the ability for something to happen existed, but it didn’t happen. The team could have won. (However, they didn’t.) eg1471/jc/dec2008 Example Modals Expressing Degrees of Possibility cannot Unlikely may/might not should must highly likely To express impossibility or near impossibility, use cannot. To express low possibility, use may/may not; might/might not; or could/could not. To express moderate possibility, use should/should not. To express high possibility or probability, use must. To express certainty or human intentions, use will/ will not. In the past context, use would/ would not. See Raimes (2006) pp. 74-75 for examples eg1471/jc/dec2008 Modals Expressing Degrees of Possibility She’s very intelligent and has been studying hard so she will pass the test. √ She’s very intelligent and has been studying hard. She should pass the test. √ She’s very intelligent and has been studying hard so she cannot pass the test. X eg1471/jc/dec2008 Modals Expressing Advisability To express whether something is a good idea or not, use should or should not. To express an advisable action that did not occur in the past, use should have + past participle. To express a past action that was not advisable, use should not have + past participle. eg1471/jc/dec2008 Modals Expressing Necessity To express necessity, use must or has/have to. I must do my homework. (Must is internal) You have to wear a seatbelt when you drive. (Have to is external) Must not expresses a prohibition, not a lack of necessity. To express lack of necessity, use do/does/did + not + have to. I don’t have to do my homework. To express a past necessity, use had to, not must . I had to do my homework last night. eg1471/jc/dec2008 Phrasal Alternatives to Modal Auxiliaries Meaning Modal Auxiliary Phrasal Alternative certainty will be going to ability can be able to advisability should had better, ought to, need to necessity must have to, have got to, be supposed to past necessity had to lack of necessity do not have to repeated past event eg1471/jc/dec2008 would used to Modal Auxiliaries Ranked by Strength Modal verb Logical probability meaning Social interaction meaning will certainty intention must logical necessity obligation would conditional certainty conditionality should probability advisability may possibility permission, possibility can possibility permission might/could low possibility eg1471/jc/dec2008 very polite permission, possibility Strength strong weak Common Error The opposite of must has two forms: eg1471/jc/dec2008 Sources Lane, A. and Lange, E. (1999). Writing Clearly: An Editing Guide (2nd ed.). Boston: Heinle and Heinle Publishers, 50-65 Raimes, A. (2006). Grammar Troublespots: A Guide for Student Writers (3rd ed.). New York: Cambridge University Press, 73-80. eg1471/jc/dec2008