【正文】
: it is a term in poetry applied to two successive lines of verse that form a single unit because they rhyme. Couplets in English are usually written in 10syllableslines, a form first used by Chaucer. This evolved into the socalled heroiccouplet popular in 17th and 18th century. The heroic couplet, two rhyming iambic pentameter lines, is also called a closed couplet because the meaning and the grammatical structure are couplet within two lines.10. Iambic pentameter: is a verse form in which a\one line of poem contains 10 syllables, which could be divided into five feet. Two syllables in one feet are stressed syllable followed by a unstressed one.