ADJ

thick, thin
pastry, pie

PHRASES

a crust of bread
We saved a few crusts of bread for the birds

ADJ

thick, thin

VERB + CRUST

form
The mud had formed a thick crust on the surface of the road

CRUST + VERB

form
Put the lid on properly, or a crust will form on the paints

PREP

~ of
a thin crust of ice

PHRASES

the earth's crust