aluminium (BrE), aluminum (AmE), gold, silver, tin
kitchen (BrE)

piece, sheet
roll

cover sth with, wrap sth in
I wrapped the sandwiches in foil.

good, ideal (esp. BrE), perfect

be, provide

as a foil
She has used mosses as a foil for the bright red flowers in the bed.

foil for, foil to
The couple provided the perfect foil for one another.