The limits of a person’s intelligence, generally speaking ,are fixed at birth, but he reaches these limits will depend on his environment.
The kind old lady offered to ________the poor homeless stranger.
It _________have rained last night, for the ground is wet.
Bob is ________crazy about Beethoven that he knows all his works well.
It’s ________great surprise to find the poor little girl lives alone in _________ countryside.
He is a clever boy, _________ has big eyes and short hair.