Content tagged with "obligation"
18 item(s) found.Modals in the main clause of third conditional sentences
Instead of would here it is possible to use could (ability or possibility), should (obligation) or might (possibility).
George could have won the race if his shoelace hadn’t come undone.
Modals in the main clause of second conditional sentences
Instead of would here we can use could (permission or ability), might (certainty/uncertainty) or should (obligation).
If you were taller, you could play for the Lakers.
If you weren’t under 18, I should punish you.
Modals in the IF-clause of first conditional sentences
In the if-clauseA group of related words containing a subject and a verb. of the first conditional we can use should (to express that the condition is less likely), can (permission or ability), will or would (willingness, insistence and refusal), must (obligation) or may (permission).
Modals in the main clause of first conditional sentences
Instead of will here we can use may/might (certainty/uncertainty), may (permission), can (permission or ability) or must/should (obligation).
BE TO + infinitive
This structureThe way in which the parts of a sentence, clause or expression are arranged. E.g.: make somebody + infinitive in "The teacher made me rewrite the composition." can express arranged eventA general term expressing that somebody or something does something or that something happens. E.g.: An apple fell on Isaac’s head.s.
The concert was to begin at 6.
However, if the planned event did not happen, we use be to + perfectThe aspect expressing completion. E.g.: He’s finished university. infinitive:
You were to have tidied your room this morning.
BE DUE TO + infinitive
When used in the past tenseA grammatical category that is marked by verb inflection. To express when an event or action happens in time or when a state exists, we use tenses., this structureThe way in which the parts of a sentence, clause or expression are arranged. E.g.: make somebody + infinitive in "The teacher made me rewrite the composition." refers to an actionA general term expressing that somebody or something does something in the past which was fixed to happen at a determined timeA concept which is related to our perception of reality; that part of existence which is measured in seconds, minutes, hours, days, weeks, etc., and which may or may not have happened.
The train was due to arrive in a few minutes.
SHOULD + perfect infinitive
You should have been on time. (but you were not)
We ought to have protected the environment. (but we did not)
These can also be considered as criticism or advice.
NEEDED TO and NEED + perfect infinitive
The past form of need to is needed to, while need as an auxiliaryA helping verb used with main verbs to express mood, voice and tense. E.g.: I can't stand when I am disturbed. ("can", "am") is used with perfectThe aspect expressing completion. E.g.: He’s finished university. infinitives only in negativeA declarative sentence indicating "no". E.g.: Tim has no friends. sentences to refer to past timeA concept which is related to our perception of reality; that part of existence which is measured in seconds, minutes, hours, days, weeks, etc.. Note the difference between didn't need to and needn't +perfect infinitive:
HAD TO
Had to expresses past obligation, both external and internal, so it can be considered the past form of both have to and must.
I had to sleep.
He had to correct his composition himself.