Cart
Start
Tart
Art
open up your heart
Dark
It is heart.
"Art" rhymes with "start" and the center of knowledge and emotion is often considered the "heart."
tart
heart part tart
Heart Hung
Heart?
heart and wise
cross my heart
That doesn't make any sense. Something that rhymes with heart would end in the sound 'art' not 'ear'. So no words.
Lemon Tart?