The dog ____attacked passers-by and therefore was kept on a chain by the owner.
Ladies and gentlemen,welcome to my program.____ me this evening is Dr.Gray.
While income worry is ____ rather common problem of the aged,loneliness is another problem that ____aged parents may face.
Many people can not learn any lessons from the mistakes____they get hurt somehow.
Everyone has periods in their lives_______everything seems very hard.
— I can’t imagine Phelps smoking marijuana (大麻).—____.