Beware of the differences, in the use of tenses, between Bristish English, BrE, and American English, AmE
• Traditionally, BrE uses the present perfect to talk about an event in the recent past and with the words : already, just and yet. In American usage these meanings can be expressed with the present perfect (to express a factor) or the simple past (to imply an expectation).This American style has become widespread only in the past 30 years; the British style is still in common use as well. Recently the American use of just with simple past has made inroads into BrE, most visibly in advertising slogans and headlines such as "Cable broadband just got faster".
o "I have just arrived home." / "I just arrived home."
o "I have already eaten." / "I already ate."
• Similarly AmE occasionally replaces the past perfect with the simple past.
• In BrE, have got or have can be used for possession and have got to and have to can be used for the modal of necessity. The forms that include got are usually used in informal contexts and the forms without got in contexts that are more formal. In American speech the form without got is used more than in the UK, although the form with got is often used for emphasis. Colloquial AmE informally uses got as a verb for these meanings—for example, I got two cars, I got to go.
• In conditional sentences, US spoken usage often substitutes would and would have (usually shortened to [I]'d and would've) for the simple past and for the pluperfect (If you'd leave now, you'd be on time. / If I would have [would've] cooked the pie we could have [could've] had it for lunch). This tends to be avoided in writing because it is often still considered non-standard although such use of would is widespread in spoken US English in all sectors of society.
Some reliable sources now label this usage as acceptable US English and no longer label it as colloquial. (There are, of course, situations where would is used in British English too in seemingly counterfactual conditions, but these can usually be interpreted as a modal use of would: If you would listen to me once in a while, you might learn something). In cases in which the action in the if clause takes place after that in the main clause, use of would in counterfactual conditions is, however, considered standard and correct usage in even formal UK and US usage: "If it would make Bill happy, I'd [I would] give him the money".
• The subjunctive mood (morphologically identical with the bare infinitive) is regularly used in AmE in mandative clauses (as in They suggested that he apply for the job). In BrE, this usage declined in the 20th century in favour of constructions such as They suggested that he should apply for the job (or even, more ambiguously, They suggested that he applied for the job). However, the mandative subjunctive has always been used in BrE.
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