comeputers are very useful in our lives,()they?A isn't B wasn't C doesn't D aren't

comeputers are very useful in our lives,()they?A isn't B wasn't C doesn't D aren't --Comeputers are so useful.They can do almost everything!--Yes.But they ___ what to doA must be told B has to be known --Comeputers are so useful.They can do almost everything!--Yes.But they ___ what to do--Comeputers are so useful.They can do almost everything!--Yes.But they ___ what to doA must be told B has to be known C．has to be known D．will know --Comeputers are so useful.They can do almost everything!--Yes.But they ___ what to doA must be told B will tell C has to be known D will know 没理解题. you are very very vicious You are very good You are very beautiful, you are very you are very good You are very silly You are very beautiful! you are very cute You are very You are very clever They are very comfortable. You are very smart.. you are very you are very clever~