From WordNet (r) 3.0 (2006) :
shed light on
v 1: make free from confusion or ambiguity; make clear; "Could
you clarify these remarks?"; "Clear up the question of who
is at fault" [syn: clear, clear up, shed light on,
crystallize, crystallise, crystalize, crystalise,
straighten out, sort out, enlighten, illuminate,
elucidate]