(i.e. not the first or last bar of a quarter) is replaced by two crotchets, one of two things happens. If there is only one syllable, both notes are sung to it in quick succession. If there are two (or occasionally more) syllables, they are split as appropriate to smoothly match the rhythm of the words to the two notes. When an internal bar has a dotted rhythm, it is to be sung as above, excepting that the crotchet can be omitted from the music if the natural rhythm of the words and the sentiment of the words indicate that it is appropriate to do so. When the first bar of a quarter has a dotted minim and a crotchet, all syllables except the last are sung to the note of the dotted minim, with the crotchet being tucked in on the last syllable before the barline. If there is only one syllable, both notes are sung to it in quick succession with the subtle emphasis being on the first note. Sometimes the last bar of a quarter has two minims instead of the usual semibreve, in which case a dot/hyphen may be required after the last barline in the text: (e.g. even as ' though they ' were mine ' ene-mies.) Particularly in long psalms, changes of chant may be used to signal thematic shifts in the words. Psalm 119, which is the longest in the psalter, is generally sung with a change of chant after every 8 of its 176 verses, corresponding to the 22 stanzas of the original Hebrew text. However, it is never sung all at once, but spread over successive days. Double, triple and quadruple chants The example above is a single chant. This is mostly only used for very short psalms (half a dozen verses or so). The most commonly used chants are double chants. These are twice the length of a single chant. The music of the chant is repeated for every pair of verses. This reflects the structure of the Hebrew poetry of many of the psalms: Each verse is in two halves – the second half answers the first; the verses are in pairs – the second verse answers the first. Triple and quadruple chants are considerably rarer. They appeared from the latter part of the 19th century to cover some of the exceptions to this format. They set the verses