Post
by shuntang » Fri Apr 30, 2004 5:27 pm
The ABC Of Using Modal Verbs
There are things we are not certain whether they happen or not. We use modal verbs to express them. Different modal verbs tell different reasons why we say an uncertainty. If a modal verb cannot meet the reasons, then it expresses pure possibility. On the other hand, if we are certain about something, we don't use modal auxiliaries to help express.
Simply put, every modal verb thus has two functions, expressing its lexical meaning and possibility.
CAN expresses ability, and if not, it expresses possibility.
MAY expresses permission, and if not, it expresses possibility.
WILL expresses willingness, and if not, it expresses possibility.
SHALL expresses opinion, and if not, it expresses possibility.
MUST expresses obligation, and if not, it expresses possibility.
OUGHT to expresses duty, and if not, it expresses possibility.
There are some more of them and you may find them in grammar books. It should be noted that their past forms are also express the same thing as their present form, yet at a even weaker degree of uncertainty.
As most future things are uncertain, we frequently use modal verbs to describe them. However, since there are also uncertainties at the present, we actually may use modal verbs at any time we need. Nevertheless, we use Modal Verb + Perfective to tell a past possibility:
Ex: They must/would/should have seen him last night.
== In such cases, we seldom use present form of modal verbs.
As there can be many shades of possibility, different situations/sentences will make the possibility look like prediction, permission, concession, certainty, probability, guess, etc. However, they are only possibility, some kind of uncertainty. Rather than from the modal verbs themselves, many meanings are derived from the sentence:
Ex: "You talk about my wife again and I must kill you."
The modal verb expresses only a possibility, but the sentence itself is a serious threat, the more so if I shout it in front of someone, pointing my finger to him. As some grammar writers will show you their ability in analysis, however, their books will list this example as the use of telling a threat, etc. This only confuses students and misleads them to nowhere.
Onerous usages will worry students, but these usage only show the confusion of the one who explains. EFLs can already speak English fluently as they start to learn grammars in schools. They therefore don't care about rules and some may go so far as to think that grammars are useless. However, ESLs depend mostly on grammars, and complicated usages would be a nightmare to them.
In my humble opinion, modal verbs are so difficult for students that we shall keep a very concise, simple view for them. It is wrong for us to display the almighty power of a sentence, and then confuse the meaning of a sentence with that of the modal verb or the tense, and finally keep quiet the role of the sentence completely. They call them "The English Verb", while the whole thing is about the SENTENCE. (Note: A few grammar writers have called his or her grammar book "The English Verb", to the same name.)
Shun