一、写出下列名词的复数形式。 1.man____ 2.f actory_____ 3.f oot____ 4.t omato_____ 5.fox ____ 6. watch____ 7.monkey____ 8.b rush____ 9.boy ____ 10. radio____ 11. baby____ 12.wife ____ 13. apple____ 14. class_____ 15.box ___ 16.bench____ 17.half ____ 18. sheep___ 19.policeman_____ 20. woman teacher ______