标准 宾语从句、状语从句、定语从句混合练习1.I dont know _or not.A. whether he is at home B. if he is at home C. that he is at home D. whether is he at home2.The man and the horse _ fell into the river were drowned(淹死). A. which B. who C. that D. of which3.I really dont know _.A. what to do B. how to do C. what to do it D. to do what 4.We couldnt find out _, so we handed it in to the teacher.A. whose pen was it B. who
