Allen and Greenough's New Latin Grammar for Schools and Colleges
J. B. Greenough, G. L. Kittredge, A. A. Howard, Benj. L. D'Ooge, Ed.

[*] a. Et, and, simply connects words or clauses; -que combines more closely into one connected whole. -que is always enclitic to the word connected or to the first or second of two or more words connected:

1. cum coniugibus et līberīs, with [their] wives and children.
2. ferrō īgnī que, with fire and sword. [Not as separate things, but as the combined means of devastation.]
3. aquā et īgnī interdictus, forbidden the use of water and fire. [In a legal formula, where they are considered separately.]

[*] b. Atque ( ac ), and, adds with some emphasis or with some implied reflection on the word added. Hence it is often equivalent to and so, and yet, and besides, and then. But these distinctions depend very much upon the feeling of the speaker, and are often untranslatable:—

1. omnia honesta atque inhonesta, everything honorable and dishonorable (too, without the slightest distinction).
2. ūsus atque disciplīna, practice and theory beside (the more important or less expected).
3. atque ego crēdō, and yet I believe (for my part).

[*] c. Atque ( ac ), in the sense of as, than, is also used after words of comparison and likeness:—

1. simul atque, as soon as.
2. nōn secus (nōn aliter) ac sī, not otherwise than if.
3. prō eō ac dēbuī, as was my duty (in accordance as I ought).
4. aequē ac tū, as much as you.
5. haud minus ac iussī faciunt, they do just as they are ordered.

For and not, see § 328. a.

[*] d. Sed and the more emphatic vērum or vērō, but, are used to introduce something in opposition to what precedes, especially after negatives (not this ... but something else). At (old form ast ) introduces with emphasis a new point in an argument, but is also used like the others; sometimes it means at least. At enim is almost always used to introduce a supposed objection which is presently to be overthrown. At is more rarely used alone in this sense.

Autem, however, now, is the weakest of the adversatives, and often marks a mere transition and has hardly any adversative force perceptible. Atquī, however, now, sometimes introduces an objection and sometimes a fresh step in the reasoning. Quod sī, but if, and if, now if, is used to continue an argument.

[*] Note.-- Et, -que, and atque (ac) are sometimes used where the English idiom would suggest but, especially when a negative clause is followed by an affirmative clause continuing the same thought: as, “—impetum hostēs ferre nōn potuērunt ac terga vertērunt” (B. G. 4.35) , the enemy could not stand the onset, but turned their backs.

[*] e. Aut, or, excludes the alternative; vel (an old imperative of volō ) and -ve give a choice between two alternatives. But this distinction is not always observed:—

1. sed quis ego sum aut quae est in mē “facultās” (Lael. 17) , but who am I or what special capacity have I? [Here vel could not be used, because in fact a negative is implied and both alternatives are excluded.]
2. “ aut bibat aut abeat ” (Tusc. 5.118) , let him drink or (if he won't do that, then let him) quit. [Here vel would mean, let him do either as he chooses.]
vīta tālis fuit vel fortūnā vel glōriā; (Lael. 12), his life was such either in respect to fortune or fame (whichever way you look at it).
3. sī propinquōs habeant imbēcilliōrēs vel animō vel fortūnā; (id. 70), if they have relatives beneath them either in spirit or in fortune (in either respect, for example, or in both).
4. aut deōrum aut rēgum fīliī; (id. 70), sons either of gods or of kings. [Here one case would exclude the other.]
5. implicātī vel ūsū diūturnō vel etiam officiīs (id. 85), entangled either by close intimacy or even by obligations. [Here the second case might exclude the first.]

[*] f. Sīve ( seu ) is properly used in disjunctive conditions (if either ... or if), but also with alternative words and clauses, especially with two names for the same thing:—

1. “ sīve inrīdēns sīve quod ita putāret ” (De Or. 1.91) , either laughingly or because he really thought so.
2. “ sīve deae seu sint volucrēs ” (Aen. 3.262) , whether they (the Harpies) are goddesses or birds.

[*] g. Vel, even, for instance, is often used as an intensive particle with no alternative force: as,—vel minimus, the very least.

[*] h. Nam and namque, for, usually introduce a real reason, formally expressed, for a previous statement; enim (always postpositive), a less important explanatory circumstance put in by the way; etenim (for, you see; for, you know; for, mind you) and its negative neque enim introduce something self-evident or needing no proof.

（ea vīta) quae est sōla vīta nōminanda. nam dum sumus inclūsī in hīs compāgibus corporis, mūnere quōdam necessitātis et gravī opere perfungimur; est enim animus caelestis, etc. (Cat. M. 77), (that life) which alone deserves to be called life; for so long as we are confined by the body's frame, we perform a sort of necessary function and heavy task. For the soul is from heaven.
1. “hārum trium sententiārum nūllī prōrsus adsentior. nec enim illa prīma vēra est ” (Lael. 57) , for of course that first one is n't true.

[*] i. Ergō, therefore, is used of things proved formally, but often has a weakened force. Igitur, then, accordingly, is weaker than ergō and is used in passing from one stage of an argument to another. Itaque, therefore, accordingly, and so, is used in proofs or inferences from the nature of things rather than in formal logical proof. All of these are often used merely to resume a train of thought broken by a digression or parenthesis. Idcircō, for this reason, on this account, is regularly followed (or preceded) by a correlative (as, quia, quod, sī, ut, nē), and refers to the special point introduced by the correlative.

malum mihi vidētur esse mors. est miserum igitur, quoniam malum. certē. ergō et eī quibus ēvēnit iam ut morerentur et eī quibus ēventūrum est miserī. mihi ita vidētur. nēmō ergō nōn miser. (Tusc. 1.9.) Death seems to me to be an evil. ‘It is wretched, then, since it is an evil.’ Certainly. ‘Therefore, all those who have already died and who are to die hereafter are wretched.’ So it appears to me. ‘There is no one, therefore, who is not wretched.’
1. “ quia nātūra mūtārī nōn potest, idcircō vērae amīcitiae sempiternae sunt ” (Lael. 32) , because nature cannot be changed, for this reason true friendships are eternal.

[*] j. Autem , enim , and vērō are postpositive ¹; so generally igitur and often tamen .

[*] k. Two conjunctions of similar meaning are often used together for the sake of emphasis or to bind a sentence more closely to what precedes: as, at vērō >, but in truth, but surely, still, however; itaque ergō, accordingly then; namque, for; et-enim, for, you see, for of course (§ 324. h).

For Conjunctions introducing Subordinate Clauses, see Syntax.

Negative Particles