Thus, and should be used with the meaning “Future-in-the-past” to express what was expected, or what actually happens after an earlier reference period. The use of should be here (like that of should be considered a future clear marker) is much less common and is generally limited to the first person. Examples: “will” and “must” are ambiguous because they are more likely to qualify the prediction of obligation. Most medical examiners now prefer the clear “must,” and I usually used it when I was a lawyer. However, if it is the word “the most misuedwordic in legal English,” it is proposed to use it entirely and replace it with must, which is now used for the engagements of animated subjects. Even if you use it systematically in the contract, another of its possible meanings can be given. From the 18th century to the 20th century, a grammar rule exchanged the meaning of the will and must be done according to the “person”. The rule was never universally respected and almost disappeared. The Oxford English Dictionary now advises that “the two words are used more or less interchangeably.” Another popular illustration is in the drama scene of Lord of the Rings, when Gandalf Balrog verified the advance with the judge`s vote of no confidence: “You must not pass”. Similarly, the will is used to express something to be expected in a general case, or something that is currently very likely: this use would sometimes be replaced (although rarely) if the subject is in the first person (under the same normative rule, that the claims apply rather than as a normal future marker for that person). This should be found in stick phrases like “I should think” and “I should expect.” However, its use in more general cases is outdated or very formal and can lead to ambiguities with the more frequent use of should. This is illustrated by the following sentences: In archaic use would have been used to display the current timer. “If I were dead,” it means “I wish I was dead.” “I`d like to fain” means “I`d love to.” Modal verbs will have been used in the past and will continue to be used in a variety of meanings.
 Although they are largely interchangeable when used only as future markers (as explained in the sections below), each of the two verbs also has certain specific uses for which it cannot be replaced by the other without changing its meaning.