11. Nursing is hard work and often low paid, but for many people it is a(n) ______________.
A. work B. employment C. vocation D. opportunity
12. On, Hoa became an art teacher.
A. ceremony B. completion C. finish D. graduation
13. ______________ trees around the house on the south and west sides, they can save up to about $$250 a year on cooling and heating.
A. To plant B. To have planted C. Having planted D. Being planted
14. We admired the Japanese ______________ the city of Fukushima after the disaster.
A. to rebuild B. of having rebuilt C. to being rebuilt D. for having rebuilt
15. They don’t forget ______________ a short vacation in Cue Phuong National Park last year.
A. to spend B. having spent C. being spent D. having been spent