237 (a). Devi = to be obliged to, to have to, means to be physically or morally obliged to do something, as:—Vi devas fari tion = You must (have to, are to) do that. Vi ne devas fari tion = You are not obliged to do that. If, however, the action is not immediate, the future tense is used for "must," as:—Vi devos fari tion morgaŭ = You must (will have to) do that to-morrow. In its Conditional form devi may be used, like other verbs, to soften an
expression, and then it can be translated by "ought," as:—Vi devus ne fari tion = You ought not to (should not) do that. Here devus is used instead of the more peremptory form, devas; Vi devas ne fari tion would mean You must not (are not to) do that (see par. [194], also pars. [237] (o), (p), on "should," "must," "ought," and par. [59] (a)).
Examples.—Mi devas vin forlasi, ĉar oni atendas min = I must (have to) leave you, for they are waiting for me. Ĉu mi devas fari tion tuj? = Must I (am I to) do that at once? Ĉu mi devos veni morgaŭ = Must I (shall I have to, am I to) come to-morrow? Mi devis skribi leteron = I had (have had) to write a letter. Li devis min vidi hodiaŭ, sed li ne povas veni = He was to see me to-day, but he cannot come. Ili devis vidi min hieraŭ, sed ili ne povis veni = They were to have seen me yesterday, but they could not come. Li estis kolera hieraŭ, ĉar li devis iri lernejon = He was angry yesterday, because he was obliged to (had to) go to school. Sed por tio ĉi mi devos atendi iom da tempo = But for this I shall have to (I must) wait some time. Se mi lin vidus, mi devus paroli kun li = If I saw him, I should have to speak to him. Se mi lin vidus, mi estus devinta paroli kun li = If I had seen (saw) him, I should have been obliged (have had) to speak to him. La celo de ĉiu estas, aŭ devus esti, bonfaradi = The aim of everyone is, or ought to (should) be, to do good. Li devus kolekti kaj aranĝi siajn faktojn = He ought to (should) collect and arrange his facts. Kiam vi estas tie, vi devus vidi la kastelon = When you are there, you ought to see the castle. Kiam vi estis tie, vi devus vidi (or, vi devus esti vidinta) la kastelon = When you were there, you ought to have seen the castle. Mi devus tute ne aŭskulti ŝin = I ought not to listen to her at all.
From these examples we see that the following is the meaning of devi in its moods and tenses. The compound forms should not be used unless absolutely necessary to render the meaning clear.
Present.
- Vi devas (paroli) = You must, have to, are to (speak).
Past.
- Mi devis (paroli) = I had to (speak); or, I was to (speak, or, have spoken).
- Mi estas devinta (paroli) = I have been obliged, or, I have had to (speak).
- Mi estis devinta (paroli) = I had been obliged to (speak).
Future.
- Mi devos (paroli) = I shall have to, I am to, I must (speak).