Light-to-moderate smokers were ________ to die of sudden heart problems than those who had never smoked.
Some researchers believe that there is no doubt______a cure for AIDS will be found.
Nowadays more people are advised to arrange for insurance_____they need medical care.
Last Monday, I was asked to give the new students a test____ their English level.
- Why do you look so worried? - My MacBook Pro broke down and my paper______unfinished since.
The athlete's years of hard working________when she finally won the Olympic gold medal.