Which lines in this excerpt from shakespeare’s romeo and juliet foreshadow the tragic ending of the play?

romeo: peace, peace, mercutio, peace!
thou talk'st of nothing.

merutio: true, i talk of dreams,
which are the children of an idle brain,
begot of nothing but vain fantasy,
which is as thin of substance as the air
and more inconstant than the wind, who wooes
even now the frozen bosom of the north,
and, being anger'd, puffs away from thence,
turning his face to the dew-dropping south.

benvolio: this wind, you talk of, blows us from ourselves;
supper is done, and we shall come too late.

romeo: i fear, too early: for my mind misgives
some consequence yet hanging in the stars
shall bitterly begin his fearful date
with this night's revels and expire the term
of a despised life closed in my breast
by some vile forfeit of untimely death.
but he, that hath the steerage of my course,
direct my sail! on, lusty gentlemen.