Paperback editions prolong its life and increase his income.是什么意思？

Paperback editions prolong its life and increase his income.

平装本延长了著作的寿命,使著作的收入有了增加.

paperback

n. 平装本，平装书；

例句
She flicked through a romantic paperback between occasional dips in the pool.
用在泳池里游一阵后歇一阵的几个空当，她翻完了一本平装本言情小说。

editions

n. 版次( edition的名词复数 )，（报纸、杂志的）一份，（广播、电视节目的）一期，（书、报、杂志等的）一版印刷总数；

例句
He became convinced of the need for cheap editions of good quality writing...
他开始相信大众对优秀作品的普及本有需求。

prolong

vt. 延长，拉长，拖延，延期；

例句
It's safe to eat foods that have been irradiated to prolong their shelf life.
食用经过辐射杀菌处理、延长了保质期的食品是安全的。

its

pron. (it的所有格形式)它的，厥；

例句
The government is to accelerate its privatisation programme.
政府将加快其私有化计划的进程。

life

n. 生活，生计，生命，性命，一生，寿命，人生，尘世；

例句
In his later life he became even more absent-minded.
他晚年变得愈加健忘了。

and

conj. 和，与，而且，于是，然后，因此；

例句
I spend a lot on expensive jewelry and clothing...
我花很多钱购买昂贵的首饰和衣服。

increase

vt.& vi. 增加，增大，增多；vt. 增强，增进，[缝纫]放（针）；vi. 增强，增进，增殖，繁殖，[缝纫]放针；

例句
Companies need to take active steps to increase exports.
各公司需要采取积极措施增加出口。

his

pron. (he的所有格)他的，(he的物主代词)他的东西；det. 属于他的，用于名词前，自己的，指某人的，上帝的；

例句
He claimed that his parents had abandoned him...
他声称父母遗弃了他。

income

n. 收入，进款，进来的动作，进入；

例句
Local taxes are going to be taking a bigger bite out of people's income than they ever have before.
地方税收在人们收入中的比重将超过以往任何时候。