PSAs are often run _____ free, and are ______ to educate people about health, safety, or any other problem that affects public welfare.
------What about going out for a walk after supper? -------______. Walking after meals is good for health.
Some of the wolves there _____ the fur.
In many countries, packets of cigarettes come with a government health warning ______ them.
We had to be patient because it ______ some time ______ we got the full results.
______ about the missing Beijing-bound Malaysian flight that he decided to look for more information about it.