quotes in act four of romeo and juliet which use imagery relating to lightness and darkness?
''Romeo and Juliet'' contains a significant amount of imagery in its various acts, relating to light/brightness and dark/darkness.
As far as Act 4 is concerned, the following images from various scenes either directly or indirectly relate to such imagery:
Scene 1: ''in the morning'', ''day'' (LIGHT); ''that very night'', ''shut me nightly in a charnel-house'', ''near-made grave'' (DARK)
Scene 2: ''cock hatch crow'd'', ''day'' (LIGHT); ''near night'', ''night'', ''tomb'', ''shroud'', ''curfew bell'', ''Death'' (DARK).
Scene 5: ''day'', ''morning'' (LIGHT), ''night'', ''black funeral'' (DARK).
Whilst most of these mightnt relate to Light/Dark in the sense of such objects as sun, moon, stars etc (as quoted in earlier acts/scenes), yet they convey all the same light and dark imagery, one way or the other, figuratively or symbolically.
Hope this helps. Im sure if you make a close further reading of the text you can also dig up more such images.