Hypothetical uses of the modals
Apart from their other meanings, the past form modals would, might and could can be used in a ‘remote’ or hypothetical sense in both main and subordinate clauses. Compare:
I will help you if I can I would help you if I could.
She may pass if she works hard. She might pass if she worked harder.
To refer to a past event have + en is used. The event is understood to be contrary to fact:
I would have helped you if I had been able to.
She would/might have passed if she had worked harder.
Should is also used, especially in BrE, as the replacement of a subjunctive in referring to states of affairs that may exist or come to happen:
It is only natural that they should want a holiday.
I am amazed he should think it is worth trying.
In the following extract from David Lodge’s novel How Far Can You Go?, in which members of a family debate possible courses of action, the modal meanings are more numerous in the dialogue than in the narrative. What is the reason for this?
Their Dad would be coming1 home the next day and they would2 have to3 look after him until he was too ill to stay out of hospital. The question was, should4 he be told?
‘How long . . . ?’ somebody wondered.5 The doctor hadn’t been specific. A matter of months rather than weeks. One could6 never be sure. ‘Who would7 tell him?’ ‘I couldn’t. I just couldn’t,’8 said their mother and wept. ‘I would,9 said Angela, ‘if we agreed that was the right thing to do.’ ‘Why tell him?’ said the youngest sister. ‘It would10 just be cruel.’ ‘But if he asks . . . ’ said another. ‘Are you going to11 lie to your own Dad?’
1past time prediction; 2past time prediction; 3obligation; 4advisability; 5doubt; 6intrinsic possibility; 7willingness; 8incapability; 9willingness; 10hypothetical; 11intention.