In my opinion, the Internet has three major drawbacks. Firstly, when you surf the Internet, your personal information, such as name, address and account can be accessed by hackers. For instance, if you use credit cards to shop online, your card information can be stolen, and then money in your account may be used up. Secondly, pornography is another serious issue, especially for teenage users. Due to the easy access to pornographic websites, teenagers may be incited to act out sexually. According to Dr. Jennings Bryant, 31 percent of male and 18 percent of female high school students admitted imitating some acts in pornography. Lastly, computers with Internet connection are likely to be infected with viruses which disrupt their normal function. It is hard to prevent virus infection although we use anti-virus programs. To sum up, information leakage, negative influences of pornography on teenagers and virus threat are three main disadvantages of using the Internet.

Nowadays, Internet has become an important part in the modern life. Besides the advantages, it also brings about many disadvantages that no one expects. First, Internet is so addictive and time-consuming. Using it sometimes makes you lose your sense of time and easily deep in meaningless things. For example, when you start studying at 7 o’clock, you have intention of using Internet for doing homework but then you are addicted to the entertainment websites and can not stop. As a result, it takes you a lot of time to finish work and makes you lazier and lazier. Second, some social networking sites contain potential risks, because they are not strictly controlled. Some websites can report the false and reactionary information, other ones even can take advantage of your belief then make money illegally. Last but not least, Internet affects harmfully to your health. It is undeniable fact that your vision is shorten so much when you use smartphone or computer so much. Moreover, it also results in some diseases, which relate to memory and skeleton, especially promote the senescence faster. Taking into consideration, Internet is not bad but everyone should uses it reasonably and effectively.
 

In my opinion, the Internet has three major drawbacks. Firstly, when you surf the Internet, your personal information, such as name, address and account can be accessed by hackers. For instance, if you use credit cards to shop online, your card information can be stolen, and then money in your account may be used up. Secondly, pornography is another serious issue, especially for teenage users. Due to the easy access to pornographic websites, teenagers may be incited to act out sexually. According to Dr. Jennings Bryant, 31 percent of male and 18 percent of female high school students admitted imitating some acts in pornography. Lastly, computers with Internet connection are likely to be infected with viruses which disrupt their normal function. It is hard to prevent virus infection although we use anti-virus programs. To sum up, information leakage, negative influences of pornography on teenagers and virus threat are three main disadvantages of using the Internet.
Phân tích
Topic sentence: In my opinion, the Internet has three major drawbacks.
Supporting idea 1: Firstly, when you surf the Internet, your personal information, such as name, address and account can be accessed by hackers. For instance, if you use credit cards to shop online, your card information can be stolen, and then money in your account may be used up.
Supporting idea 2: Secondly, pornography (sách báo khiêu dâm) is another serious issue, especially for teenage users. Due to the easy access to pornographic websites, teenagers may be incited (bị xúi giục) to act out sexually. According to Dr. Jennings Bryant, 31 percent of male and 18 percent of female high school students admitted imitating (bắt chước) some acts in pornography.
Supporting idea 3: Lastly, computers with Internet connection are likely to be infected (bị nhiễm) with viruses which disrupt their normal function. It is hard to prevent virus infection although we use anti-virus programs.
Concluding sentence: To sum up, information leakage (kẽ hở), negative influences of pornography on teenagers and virus threat are three main disadvantages of using the Internet.
Ngôn ngữ trong văn nghị luận
Khi đưa ra quan điểm, người viết nên sử dụng các lối diễn đạt:
In my opinion/ From my point of view, ... (Theo tôi/ theo quan điểm của tôi ...)
I believe that/ I think that ... (Tôi tin rằng...)
I (dis)agree with the opinion that ... (Tôi (không) đồng ý với quan điểm ...)
Liệt kê các luận điểm bằng các từ/ cụm từ nối sau:
First/ Firstly/ First of all/First and foremost/ To begin with, ... (Thứ nhất ...)
Second/ Secondly, ... (Thứ hai ...)
Third/ Thirdly, ... (Thứ ba ...)
Next/ Then, ... (Tiếp theo là ...)
Finally/ Lastly/ Last but not least, ... (Cuối cùng là ...)
Đưa ra dẫn chứng:
To illustrate/ For example/ For instance, ... (Ví dụ ...)
Tổng kết lại nội dung:
In conclusion/ In short/ To sum up/ In summary, ... (Kết luận là ...)
For the reasons above, ... (Từ những lý do nêu trên ...)
_nguồn Tiếng anh 123_
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in my opinion, the Internet has three major drawbacks. Firstly, when you surf the Internet, your personal information, such as name, address and account can be accessed by hackers. For instance, if you use credit cards to shop online, your card information can be stolen, and then money in your account may be used up. Secondly, pornography is another serious issue, especially for teenage users. Due to the easy access to pornographic websites, teenagers may be incited to act out sexually. According to Dr. Jennings Bryant, 31 percent of male and 18 percent of female high school students admitted imitating some acts in pornography. Lastly, computers with Internet connection are likely to be infected with viruses which disrupt their normal function. It is hard to prevent virus infection although we use anti-virus programs. To sum up, information leakage, negative influences of pornography on teenagers and virus threat are three main disadvantages of using the Internet.

In my opinion, the Internet has three major drawbacks. Firstly, when you surf the Internet, your personal information, such as name, address and account can be accessed by hackers. For instance, if you use credit cards to shop online, your card information can be stolen, and then money in your account may be used up. Secondly, pornography is another serious issue, especially for teenage users. Due to the easy access to pornographic websites, teenagers may be incited to act out sexually. According to Dr. Jennings Bryant, 31 percent of male and 18 percent of female high school students admitted imitating some acts in pornography. Lastly, computers with Internet connection are likely to be infected with viruses which disrupt their normal function. It is hard to prevent virus infection although we use anti-virus programs. To sum up, information leakage, negative influences of pornography on teenagers and virus threat are three main disadvantages of using the Internet.

In my opinion, the Internet has three major drawbacks. Firstly, when you surf the Internet, your personal information, such as name, address and account can be accessed by hackers. For instance, if you use credit cards to shop online, your card information can be stolen, and then money in your account may be used up. Secondly, pornography is another serious issue, especially for teenage users. Due to the easy access to pornographic websites, teenagers may be incited to act out sexually. According to Dr. Jennings Bryant, 31 percent of male and 18 percent of female high school students admitted imitating some acts in pornography. Lastly, computers with Internet connection are likely to be infected with viruses which disrupt their normal function. It is hard to prevent virus infection although we use anti-virus programs. To sum up, information leakage, negative influences of pornography on teenagers and virus threat are three main disadvantages of using the Internet.
 

Internet can be considered as one of the greatest inventions of mankind in the 20th century. All of the things that Internet had been given us have never stopped the world from being surprised. With an extremely huge database of information and has been constantly updated every day, it is true to say that the Internet is an ocean of ​​knowledge which is never exhausted. The big men who dominate the Internet including Google, Wikipedia, YouTube, Facebook, Twitter, Instagram etc., and they can satisfy almost all of the curiosity of anyone. We can find almost every information, from society, science, astronomy, geography to methods for cooking, make-up, or even personal information of a person who is completely a stranger to us. Internet provides an effective learning and researching environment if we know how to use it suitably. Besides studying, we can also search interesting resources of entertainment on the websites. Nowadays, most of the entertainment programs are posted online in large numbers, so it will not be difficult for us to find joy for ourselves. In short, the Internet is a powerful assistant for finding and sharing information for people.