30．Many businesses offer membership cards to clients，promising that they will enjoy discounts，and the more they use the cards，the bigger the discounts will be．This is a common practice to attract and keep regular customers．By providing quality products or services at reasonable prices，businesses can indeed achieve this goal．
However，in recent years，consumers trying to book flights or hotels on certain websites have discovered that prices were actually higher for frequent users than for newcomers．They fund that they could pay less by opening up a new account rather than using an old one．Unfortunately，these businesses are using information gathered through big data on clients' preferences and purchasing habits to take advantage of them，which amounts to targeted price discrimination．
There have been numerous cases of overcharging based on big data on various shopping platforms in recent years．However，since it's difficult to collect sufficient evidence to accuse these businesses，only a small number of consumers have chosen to take them on．Thus，big data，which is supposed to benefit the public，is helping some businesses cheat consumers．Big data itself is not a bad thing，since it is playing an increasingly important role in social life and economic growth．It can serve as a basic resource and tool．But since it is being used to overcharge frequent clients，the public has expressed anger．It's a short-sighted behavior that will eventually drive away customers．Instead，big data should be used to improve businesses' services and products by strengthening supervision（監(jiān)督） and punishment so that this new technology can play its due role in Internet commerce．
It's urgent to stop the misuse of big data by stepping up supervision．Market and network supervisory authorities need to join hands in this effort．The illegal use of big data should be severely punished．Advanced technology should be more widely used to supervise big data use．
It's all right for businesses to employ certain methods to make big money，but to charge regular clients more than newcomers by taking advantage of information collected through big data analysis is violating regular clients' rights as well as their trust in these businesses．The Law on the Protection of Consumer Rights and Interests clearly states that consumers have the right to know the truth about the commodities and services they buy．Thus，to overcharge regular clients is not only betraying the principle of fairness and sincerity，but also relevant laws．In the long run，it's the businesses that will suffer most．
How Do We Make Good Use of Big Data in Commerce
| Passage Outline |
Supporting details |
| A common practice |
Businesses，which promise quality products with lower costs，offer membership cards with the （1） of appealing to regular customers． |
| A reality （2） to expectations |
●Newcomers can enjoy a（3） discount than frequent clients by registering a new account．
●Personal information gathered，clients have fallen （4） to targeted price discrimination． |
| The role of big data in social and economic life |
●Despite （5） of hard evidence，there have been lots of cases where companies overcharge customers with the help of big data．
●Playing its due role，big data can （6） both businesses and the public． |
| （7） to discouraging misuse of big data |
●Market and network supervisory authorities should make（8） efforts．
● Severe （9） is necessary to fight against the illegal use of big data with the wide application of advanced technology． |
| Conclusion |
Overcharging regular clients violates the principle of fairness and relevant laws，which，in the long run，will be most （10） to business． |
