1：This coat______ me one hundred and sixty yuan.
1.spend
2.cost
3.take
4.pay
2：It was in that small village______our president was born.
1.which
2.when
3.that
4.as
3：The audience, most of ____ were students, enjoyed the performance very much.
1.whom
2.who
3.which
4.that
4：Little______that they had made a great discovery in chemistry.
1.they realized
2.had they realized
3.did they realize
4.they had realized