I think____necessary to learn English well.A、itsB、itC、thatD、that is

I think____necessary to learn English well.A、itsB、itC、thatD、that is The boss made the workers___ten hours a day.A.work B.to work C.working D.worked2.____you____next week?A.Are;going to free B.Are;going to be free C.Are;going free D.Do;free3.I think____necessary for us to learn English well.A.it B.its C.that D.that's4 Sue,do you think____necessary to wait for your turn?----Of course.A.it B.this C.that D.| i i I I, I I I i i i i -I I i i