根据括号内所给汉语写出单词的正确形式。

1. Sunday is the              (第一)day of the week.

2. Can you             (写)them on the blackboard?

3. Li Dong often              (练习)his spoken English in or out of the class.

4. There are two small            (城市) near my hometown (家乡).

5. Don't               (关闭)the window,it's very hot.

材料采购合同约定先交付材料后付款结算，若合同履行过程中供货方交付的材料质量不符合约定的标准，采购方有权拒付贷款，这是材料采购方行使的( )。

A．同时履行抗辩权
B．不安抗辩权
C．后履行抗辩权
D．先履行抗辩权