用括号内所给动词的适当形式填空。
1. Betty is often seen ______ (help) the old man with his housework.
2. He prefers ______ (take) part in the public activities rather than stay at home alone.
3. They ______ (agree) with each other, so they argued for a long time.
4. Animals are our friends, so ______ (protect) them is our duty.
5. You have ______ (award) a scholarship to study violin at our school of music.
