A growing number of people are beginning to believe that learning new skills and knowledge _____ more promotion opportunities.
It is ______ that the noise around us is a(n) _______ to our health and well being.
We can broaden our horizons through _________ to new things.
Jack’s house has been broken into twice and now he takes________ against theft at any time.
The environmental organization calls on customers not to purchase these _______ packages of food, clothes and gifts.
People are advised not to smoke at home, since passive smoking is ________ to people around them. Which is Not proper for the blank?