Anacrusis

=//Anacrusis//= One or more syllables at the beginning of poetry that are not regarded as part of the metrical pattern (simply considered a prelude or “pickup” to the meter)

“Waiting” by Robert Frost, lines 22-24
“And tries once—twice—and thrice if I be there; And on the worn book of old-golden song I brought not here to read, it seems, but hold”

The first two syllables of each line seem to have a “pickup” feel to them, as they lead into the rhythm of the lines. Each line follows the lead-in syllables with spondees, followed by three trochees. The effect is to make the narrative sound like a continuing progression of events, as though the speaker is unconsciously falling into the next action. This relates to the general tone of the poem, of timelessness and everlasting patience.

“King Lear” by William Shakespeare, Act V, Scene 3, Lines 63-65 (Edmund's lines)
“We sweat and bleed. The friend hath lost his friend, And the best quarrels in the heat are cursed By those that feel their sharpness.”

In the first and third line (and, indeed, in the rest of Edmund’s dialogue in this scene), the line begins with an iamb (unstressed/stressed). But in the second line, we see that the “And” acts as an anacrusis because only when we remove it does the line commence with an iamb like the rest of Edmund’s lines here (“And the best” is unstressed-unstressed-stressed). The “And” acts as a pickup to the metrical pattern.The effect is to give Edmund's line a sense of haste, of an urge to get his words out. Shakespeare does this because, truly, Edmund is eager to advance himself in the eyes of Regan and Albany.

Information Sources: www.dictionary.com, en.wikipedia.org Picture Source: ([|http://shakespeare-art-museum.com/Drawings/d09.jpg)]

This page by James Mao