But if, on the other hand, two closely connected parts of a sentence are each of them long enough to fill up two measures, they may be separated by enjambement: _Whan Zéphirús eek wíth his swéte bréethe Enspíred háth in évery hólte and héethe The téndre cróppes, ánd the yónge sónne Háth in the Rám his hálfe cóurs irónne_, &c. Chauc. Prol. 5-8. _There áre a sórt of mén, whose vísagés Do créam and mántle líke a stánding pónd._ Shakesp. Merch. I. i. 88-9. The admissibility or inadmissibility, however, of run-on lines depends on many different and complicated considerations, for which the reader may be referred to ten Brink, _Chaucer's Sprache und Verskunst_, §§ 317-20, and to our own larger work, vol. ii, pp. 59-62. In Shakespeare's versification, and probably also in that of other poets, the more or less frequent use of run-on lines is characteristic of certain periods of their literary career, and is therefore looked upon as a valuable help in determining the date of the different plays (cf. § 91). The largest percentage of run-on lines probably occurs in Milton's epics. § =93.= The judicious use of run-on lines is often resorted to for the purpose of avoiding monotony. Another metrical licence connected with the line-end, which is adopted for the same purpose, is =rhyme-breaking=. This occurs chiefly in rhyming couplets, and consists in ending the sentence with the first line of the couplet, instead of continuing it (as is usually done) till the end of the second line. Thus the close connexion of the two lines of the couplet effected by the rhyme is broken up by the logical or syntactic pause occurring at the end of the first line. This is used rarely, and so to say unconsciously, by the earlier Middle English poets, but is frequently applied, and undoubtedly with artistic intention, by Chaucer and his successors. The following passage contains examples both of rhyme-breaking and of the more normal usage: _A Yéman hádde he, ánd servántz namó At thát tyme, fór him líste ríde sóo; And hé was clád in cóte and hóod of gréne: A shéf of pécok árwes bríght and shéne Únder his bélt he bár ful thríftilý. Wél koude he drésse his tákel yémanlý;_ &c. Chauc. Prol. ll. 101-6. Rhyme-breaking may, of course, also take place in other metres, as e.g. in four-foot iambic verses: _Which hópe I kéep full súre in mé, As hé, that áll my cómfort ís. On yóu alone, which áre my blíss_, &c. Surrey, pp. 79-80.