单选题 Bananas are widely believed to grow on trees: this is incorrect. The banana is a plant which finishes all its growth in one year, reaching a height of 30 feet. Bananas have a subterranean (地下的) stem from which come large, green leaves. The plant reaches its maturity in about 18 months.
As the bunches of bananas mature and the fruit develops, they can be propped (支撑) up with poles and covered with blue polyethylene (聚乙烯) bags. These prevent injury, protect against the frost, and speed ripening by increasing heat and humidity.
Once the bananas plant has produced its fruit, the mother plant dies and is replaced by pups (sucker plants). These grow next to the parent and make a new generation of banana plants.

单选题 What would be the best title for this passage?

A、 Beliefs About Banana Plants
B、 The Growth of a Banana Plant to Maturity
C、 A Year in the Life of a Banana Plant
D、 Bananas Plants: from Birth to Maturity

单选题 Why are "blue polyethylene bags" mentioned in paragraph 2?

A、 They are used to prop up bananas.
B、 They protect growing bananas and speed ripening.
C、 They help increase heat and humidity and so prevent injury.
D、 Bunches of bananas are always covered with them.

【正确答案】 B

【答案解析】[解析] 第二段主要讲述用蓝色聚乙烯袋来保护生长的香蕉，使其加速成熟，故选B。

单选题 What is the main idea of the last paragraph?

A、 How the banana plant produces its fruit.
B、 How a sucker plant is called a pup.
C、 The death of mother plants.
D、 The growth of sucker plants.

【正确答案】 D

【答案解析】[解析] 最后一段的意思并不是只说母体的死亡，而主要是告知我们(新老交替)下一代幼芽又生长出来。所以选D不选C。A、B就更偏离题意了。

单选题 Another way of expressing the last sentence underlined is ______.

A、 sucker plants grow beside the parent plant and create new banana plants
B、 a new generation of parent plants grows next to the sucker plants
C、 growing next to the parent plant helps sucker plants make a new generation of banana plants
D、 parent plants have sucker plants growing beside them: two generations of plants thus grow together