Knowledge is to one’s mind ______ food is to one’s body

One theory this phenomenon acupuncture reduces pain suggests that acupuncture_____ pain signals from reaching the brain.

Have you worked here since you graduated?—No, I ________ at a factory in Beijing for six years

There will be ____ cars and ____ pollution twenty years later.

I don’t know what I _______ without the suitcase you lent me.–Glad to have been of some help to you.