听力每日练习 listen 2768 Light or heavy use

1-- I've just got a new printer. How often do I need to replace the print heads?
 
2--Well, under normal conditions each head lasts about 5 000 copies or so. It depends on the user, but about once a month is average.
 
1-- So if I don't print out very much, it could last a lot longer?
 
2-- That's right. It could last six months or more. This model's designed for heavy use. Don't worry - you'll get an error message telling you when to change the head.
 
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注解：
 
1.printer打印机
2.normal conditions正常情况
3.designed 设计
 
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译文：
 
1--我刚买了个新的打印机。我多长时间需要更换一次打印头？
2--哦,在正常情况下每个打印头能够打印5000张左右。这要看用户的具体情况了，但是一般平均一个月一次。
1--那么如果我打印的不是很多，它能使用很长时间吗？
2--对。可以用六个月以上。这个模块的设计是为重型打印机使用的。不用担心，你会得到错误信息什么时候需要更换打印头。