Legend has it that the final words of French grammarian Dominique Bouhours were, "Je vais ou je vas mourir; l'un et l'autre se dit, ou se disent." In English that would be, "I am about to--or I am going to--die. Either expression is used."
As it happens, there are several ways of expressing the future in English, including the use of:
- the simple present: We leave tonight for Atlanta.
- the present progressive: We're leaving the kids with Louise.
- the modal verb will (or shall) with the base form of a verb: I'll leave you some money.
- a semi-auxiliary such as to be going to or to be about to: We are going to leave your father a note.
This may sound paradoxical (if not linguistically pessimistic), but it all hinges on the way we define tense. I'll let David Crystal explain:
How many tenses of the verb are there in English? If your automatic reaction is to say "three, at least"--past, present, and future--you are showing the influence of the Latinate grammatical tradition. . . .
[I]n traditional grammar, [t]ense was thought of as the grammatical expression of time, and identified by a particular set of endings on the verb. In Latin there were present tense endings . . ., future tense endings . . ., perfect tense endings . . ., and several others marking different tense forms.
English, by contrast, has only one inflectional form to express time: the past tense marker (typically -ed), as in walked, jumped, and saw. There is therefore a two-way tense contrast in English: I walk vs I walked--present tense vs past tense. . . .
However people find it extremely difficult to drop the notion of "future tense" (and related notions, such as imperfect, future perfect, and pluperfect tenses) from their mental vocabulary, and to look for other ways of talking about the grammatical realities of the English verb.
(The Cambridge Encyclopedia of the English Language. Cambridge University Press, 2003)
So from this perspective (and keep in mind that not all linguists wholeheartedly agree), English has no future tense. Fortunately, however, it does have plenty of other methods for expressing future time.
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