He has ______ friends.He always keeps himself alone at home.
—If not controlled, some terrible diseases will spread in the stricken areas after the terrible earthquake. —So people there are in _____ need of medical teams.
Foreign trade, the ____ of goods between nations, takes place for many reasons.
The famous professor’s lectures, though ____ informal, are considered far more informative and interesting.
____ through Africa, the infectious disease jumping from children to adults killed 1,000 people.
Now more people prefer a house in a coast city to ____ in such a large city as Beijing.