Lines can be either end-stopped or enjambed. End-stopped lines put a clear rhythmic break at the end of each line, often reinforced by a comma or period. William Wordsworth's "She Dwelt Among the Untrodden Ways" is end-stopped, ending

  She lived unknown, and few could know

    When Lucy ceased to be;

  But she is in her grave, and, oh,

    The difference to me!

The fact that the reader is trained by the ballad meter of the poem reinforces the lament of the last two lines: because the meter makes sure the "oh" is end-stopped, the sigh lingers a touch longer than it would in an enjambed poem. Wordsworth's "Tintern Abbey," on the other hand, is generally enjambed. It begins,

Five years have passed; five summers, with the length

Of five long winters! and again I hear

These waters, . . . 

The running enjambment of the blank verse in "Tintern Abbey" creates a special emphasis for the few end-stopped lines. (Blank verse is unrhymed iambic pentameter.)