1.Let’s buy our tickets while I still have ___.

　　A. a little money to leave B. little money left

　　C. a few dollars left D. few dollars to leave

　　【答案】C。B項和D項中的little和few均為否定含義，與句意不符，排除。C項為have sth. left用法，意思是：“還剩下……”。這里have a few dollars left的意思是“還剩下幾個美元”，left的過去分詞是leave，它的賓語是前面的a few dollars。句意為：我們買票吧，盡管我們這只剩幾美元了。while：盡管。

　　2. We shall ask for samples ___ and then we can make our decision.

　　A. to be sent B. being sent C. to sent D. to have been sent

　　【答案】A本句考查非謂語動詞做賓語補足語，因為是將來式，所以用動詞不定式做賓補，又因為賓語和賓語補足語之間是邏輯上的動賓關系，因此用動詞不定式的被動。本句的意思是：“我們要求把產(chǎn)品的樣品送來，然后我們可以做出決定。”

　　3. Some cities have passed laws that allow coal and oil ____ only if their sulfur content is low.

　　A. burning B. to burn C. being burned D. to be burned

　　【答案】D。本題考查的是allow sth. to be done，主動形式是allow sb to do sth.此處是允許人們在硫含量低的情況下燃燒煤和石油，所以它們是被燃燒，用被動。

　　4. Mother warned the electric lamp.

　　A. not to touch B. him not to touch C. him not touching D. him not touch

　　【答案】B不定式的否定式。warn sb.. not to do sth..屬于固定搭配。意為“警告某人不要做某事”。

　　5. Don't leave the water ________ while you brush your teeth.

　　A. run B. running C. being run D. to run

　　【答案】B。別讓水一直流著。