A 20-year-old junior at Georgia Southern University told BuzzFeed News that she normally spends $500-600 on access codes for class.

2018年6月四级真题（第三套）阅读 Section B

As universities go digital, students are complaining of a new hit to their finances that's replacing—and sometimes joining—expensive textbooks: pricey online access codes that are required to complete coursework and submit assignments.

2018年6月四级真题（第三套）阅读 Section B

But critics say the digital access codes represent the same profit-seeking ethos (观念) of the textbook business, and are even harder for students to opt out of.

2018年6月四级真题（第三套）阅读 Section B

Changing building codes, evolving tastes, and the high cost of maintaining those wonderful old signs have businesses embracing LEDs, which are energy efficient, but still carry great cost.

2018年6月四级真题（第一套）阅读 Section A

David Hunt, an associate professor in sociology at Augusta University, which has rolled out digital textbooks across its math and psychology departments, told BuzzFeed News that he understands the utility of using systems that require access codes.

2018年6月四级真题（第三套）阅读 Section B

Digital learning systems now charge students for access codes needed to complete coursework, take quizzes, and turn in homework.

2018年6月四级真题（第三套）阅读 Section B

Many of the access codes he's purchased have been required simply to complete homework or quizzes.

2018年6月四级真题（第三套）阅读 Section B

Some colleges have what they call an "honor code", though if you are smart enough to get into these schools, you are either smart enough to get around any codes or hopefully, too ethical to consider doing so.

2017年12月四级真题（第一套）阅读 Section B

If, for example, building codes included green construction guidelines, most developers would be too lazy to challenge them.

2015年12月六级真题（第二套）阅读 Section B

In war time, codes are especially important.

2018年6月六级真题(第二套)听力 Section B

As long as there have been codes, people have tried to break them.

2016年高考英语全国卷1 阅读理解 七选五 原文

People have used secret codes for thousands of years.

2016年高考英语全国卷1 阅读理解 七选五 原文

Secret codes keep messages private。banks, companies, and government agencies use secret codes in doing business, especially when information is sent by computer.

2016年高考英语全国卷1 阅读理解 七选五 原文

So codes must be changed frequently.

2016年高考英语全国卷1 阅读理解 七选五 原文