___ against cancer for many years, Steve Jobs, the co-founder of Apple, who died at the age of fifty-six, made technology fun.

Everyone in our class works as hard as they can ________ to enter a good college.

___in a heavy snow, the couple had to walk home, leaving their car behind.

Alcohol is also classified as a downer (镇静齐Ij), and though it is legal, it can damage the liver and do great harm if   in large quantities.

______ to nuclear radiation, even for a short time, may influence genes in human bodies.