It is the prevention of disease_____ its successful treatment that has led to the rapid increase of the world’s population

“ ”is used for saying that what you do is more important than what you say you will do.

He said to us that he ____the teacher’s instructions

The people in my village ________ the income from their fruit sales.[ ]

He is rather difficult to make friends with, but his friendship, ____, is more true than any other.