dal always appears in its basic form (for example, "could have gone" instead of "could had gone"). Time use of preterite forms.forms may be used when referring to situations seen from the perspective of an earlier time. For example, would is originally the past tense of will, and it can still be used in that sense. The statement "People think that we will all be driving hovercars by the year 2000", in the context of the 1960s, can be represented in the present by replacing the verbs in italics by the appropriate preterite forms: "In the 1960s, people thought we would all be driving hovercars by the year 2000. "Likewise," I can do that "may become" I could do that when I was younger, but not anymore. "preterite forms can also be used in the apodosis in the conditional mood, such as in counterfactual conditionals: "If they wanted to do it, they would have done it by now." "If you bought a bus pass, you could catch as many buses as you liked without worrying about the cost of the fares. "" If he were more polite, he might be better liked. "is not always an explicit protasis (" if "clause) in this use:" Someone who likes red and hates yellow would probably prefer strawberries to bananas "means the same as" If someone who liked red and hated yellow were offered a choice of fruit, he or she would probably prefer strawberries to bananas. "" I could help you with your work "gives a more tentative sense of ability to help than, say," I can help you with your work "would. The implied protasis could, depending on the context, be along the lines of "If I wanted to". And willalso: Shall and willis used in many of the same senses as will, though not all dialects use shall productively, and those that use both shall and will generally draw a distinction (though different dialects tend to draw different distinctions). In standard, perhaps old-fashioned English, shall in the first person, singular or plural, indicates mere futurity, but in other persons shows an order, command or prophecy: "Cinderella, you shall go to the ball!" It is , therefore, impossible to make shall questions in these persons. Shall we? makes sense, shall you? does not.derives from a main verb meaning to owe, and in dialects that use both shall and will, it is often used in instances where an obligation, rather than an intention, is expressed.is also used in legal and engineering language to write firm laws and specifications as in these examples: "Those convicted of violating this law shall be imprisoned for a term of not less than three years nor more than seven years," and "The electronics assembly shall be able to operate within its specifications over a temperature range of 0 degrees Celsius to 70 degrees Celsius. "is commonly used, even in dialects where shall is not. The negation is "should not" (or the contraction "shouldn't"). Can describe an ideal behaviour or occurrence and imparts a normative meaning to the sentence; for example, "You should never lie" mean...
