Answer the following questions (a) in the affirmative (b) in the negative, in each case
repeating the auxiliary and using a pronoun as subject.
Do you need this? ~ Yes, I do/No, I don't.
Can Tom swim? - Yes, he can/No, he can't.
Is that Bill? ~ Yes, it is/No, it isn't.
Will there be time? ~ Yes, there will/No, there won't.
Use needn't in 7 and 15....