CONJUGATE. 295 CONJUNCTION. are anv two angles whose sum is 360°, as 10° and 3ob°, 400° and —40°, 180° and 180°. Con- jugate pvhi'ts with respect to a conie are points eac'li of whieli lies on the pohir of the other. (See Circle.) A conjugate hyperbola is one which has for its transverse and conjugate diameters the conjugate and transverse diameters of a given hj-perbola. The equations of an hyperbola and its conjugate hyperbola are related thus: If -^ '■— =: 1 be the equation of the given hyper- bola, then -t; — ^ — — 1 is the equation of its conjugate. Conjugate Jines, with respect to a conic, are lines each of which passes through the pole of the other. Conjugate axes or diameters of a tonic are diameters which are conjugate lines with respect to the conic. Conjugate trianylcs with respect to a conic are triangles such that the sides of each are the polars of the vertices of the other and the vertices of each are the poles of the sides of the other. Conjugate points in a harmonic range are a pair of points harmonically separating two others. Thus, if A, P, B, Q, are four collinear points such that AP:PB = AQ:BQ, P and Q are called haruionic conjugates. Simi- larly in a harmonic pencil of four rays O (APBQ), OP and OQ are conjugate rays. (See Aniiakmokic Ratio.) Conjugate elements of a determinant (q.v. ) are those elements which are symmetrically situated with respect to the prin- cipal diagonal. Certain forms of quanties are also called conjugate. CONJUGATE FOCUS. See Light. CONJUGATION (Lat. conjugatio, combina- tion, from coiijiigarr, to .yoke together), IN Plants. A kind of fertilization, in which there is no distinction between the male and the female cells (gametes) . It is restricted to certain low- forms of alg!E and fungi (qq.v.). See Fertil- ization. CONJUGATION. A term in grammar ap- plied to a connected view or statement of the changes of form that a verb (q.v.) undergoes in its various relations. (See Inflection'.) The forms usually included under this term are those ■ that serve to mark : ( 1 ) Person, or the distinc- tion between the speaker, the spoken-to, and the spoken-of: as (T) write, (thou) writcst, (he) writes. (2) Number; as (.John) lorites, (they) write. ( 3 ) Tense, or time ; as ( 1 ) torite, tiyrote, have icritten, shall icrite. (4) Mood, or the manner in which the action is presented. When the action is simply asserted, it is the indicative mood, as (he) irrote: when put as a supposition or condition, it is the conditional or subjunctive mood, as if he icrote. The imperative mood ex- presses a command or request, and is generally used only in the second person, as write. The infinitive mood expresses the action without limi- tation of any kind — to irritc: as it makes no affirmation, it is, strictly speaking, not a verb, but a kind of abstract noun. The two participles, the one expressing the action as in progress Urriting] , the other as completed (irritten), may be classed with the infinitive, as not affirm- ing an-thing. The infinitive and the participles are sometimes called verbals. In opposition to the infinitive and the participles, the other parts of the verb are called finite. (.5) Voice, or dis- tinction between active and passive (see Verb) ; as (he) iirote (the letter), (the letter) was written (by him) . In English, and in nuist modern Kuropciui languages, the greater part of these distinctions are indicated by separate words; in Sanskrit, Creek, and Latin they were nearl.y all indicated by prefi.xes and suffixes, or other modifications of the word itself. The nature and origin of these modifications are considered under the head Inflection. All verbs do not take the sauie changes, even in the same language. Although the suffixes, e.g., may have originally been the same, yet they underwent, in course of time, diflferent kinds of corruption or obliteration, de- pending upon the nature of the sounds in the root verb. This leads to the verbs of a language being arranged in difl'erent classes or conjuga- tions. In Latin, for instance, granuiiarians recognize four conjugations, and verbs lliat can- not be brought into any class are called irregular verbs. In English there are two distinct types of the inflections of verbs; thus, / love becomes in the past tense 7 loved, and in the passive voice [ am loved; while he shakes becomes he shook and he was shaken. Verbs that, like lore, take d (or ed — sometimes t) in their past tense and past participle form one class or conjugation, and those resembling shake in their changes form another. The former class is by far the more numerous ; but the latter includes the most com- monly used and oldest verbs in the language. The mode of change seen in shake, shook, .shaken is believed to be more ancient than the other, and is therefore sometimes called the old conjuga- tion, but more generally the 'strong" conjugation, the other being the new or weak. The termi- nology reguliir and irregular is incorrect. The verbs belonging to tlie old conjugation are all of Saxon origin, and are primitive or root verbs; while derivative verbs belong to the other class. Verbs of the weak conjugation are pretty uniform in taking d or ed, although after certain sounds the d is of necessity pronounced as t, and is some- times replaced by that letter in writing — dreamt For the vowel change in the strong conjugation, see Abl.ut. For furtlier information on tlie con- jugation of English verbs, consult: Lounsbury, English. Language, rev. ed. (New York, 1894); Emerson, Historg of the English Language (New York, 1804) ; 'Skeat, Principles of English Etymology, vol. i. (London. 1887) ; and for language in general, Strong. Logeman, and Wheeler, Lntrodaetion to the Study of the His- tory of Language (New York, 1891). See Graii- M.R and Inflection. CONJUNCTION (Lat. conjunctio, from con- jungere, to join together, from com-, together + jungcrc, to join: connected with Lat. juguin, yoke). One of the parts of speech, or classes into which grammarians divide words. Conjunc- tions serve the purpose of connecting sentences, parts of sentences, and single words : as 'Day ends and night begins. William and John learn Latin. Charles and .James carried the basket between them.' In the first sentence, and con- nects two separate affirmations into one com- pound sentence. The same is true in the second — the separate affirmations being. 'William learns Latin.' and '.John learns Latin.' In the third sentence, and connects only the two words 'Charles' and '.Tames,' as it cannot be affirmed of either of them alone that he 'carried the
