Only when _____ possible to settle the problem.
.The boys started the song,and then the girls _________ in a loud voice.
The sports meet has been _________ because of the thick fog,so we’ll have our lessons in our classroom.
Everyone passed the exam.It _________ difficult.
.Beginners of English can _________ quite well without learning any grammar rules.
.The _________ look on his face suggested that he hadn’t expected _________ would happen.