.The house caught ______ fire while they were away. It must have been set ______ on fire by someone.
If you had seen Mr. Chang at the meeting, you __ what to do now.
All of us went to the park ___ Hsiao Wang .He was ill at that time.
Mr. Chang is not only a teacher, ___ a writer.
In our school only teachers are allowed to use this room. And only in this room __ find some good dictionaries.
My friend, Tom, bought __ oar.