my son is busy ___ homework onweekends?（do .does.to do.doing

my son is busy ___ homework onweekends?（do .does.to do.doing Tony is busy-----his homework.A.doing B.do C.to do D.does his son is often made()a lot of homework.a.does b.do c.to do She is busy ( )her homework.A.doing B.to du C.do I want ___ homework now.A.doing B.to do C.to do my D.do my but he has to 【】 his homework first A.do B.does C.doing D,is 是busy to do 还是busy doing My homework ___(do) already I am busy __(do)my homework. I'm busy ______(do)my homework it is my job doing/ to do? my job is to do 还是doing