---Have you seen toothpaste?-Isn’t it on sink?A. the; aB. /; theC. the; theD. /; a

问题补充：

---Have you seen toothpaste?

---Isn’t it on sink?

A. the; a

B. /; the

C. the; the

D. /; a

答案：

A. the; a

B. /; the

(答案→)C. the; the

D. /; a

解析：考查冠词。句意：—你看到那个牙膏了吗？—它不是在水池上吗？结合语境可知两空都是特指说话双方都知道的事物。故用定冠词，选C。