I forgot to include the following sentences,please. Thank you very much for your help.

1) However, European law says that animal testing cannot be used for beauty and cleaning products.
2) Those who support animal testing say that it is a necessary evil since it helps scientists to develop vaccines as well as new surgical techniques.
3) Those who oppose animal testing say that it is not always reliable because an animal’s response to a drug can be different from a human’s. Furthermore, there are many cases of scientists causing pain to animals when they do experiments.
4) In their opinion human life is more important than the life of an animal. There are alternatives to animal testing. Some experiments use computer models and programmes.
5) Human tissue can also be used to test drugs. Other methods include analysing statistics.
6) Many animal rights groups break the law to try to stop animal testing. There are even animal rights terrorists are people who attack research centres and intimidate workers

1) OK

2) OK

3) Those who oppose animal testing say that it is not always reliable because an animal’s reaction to a drug can be different from a human’s. Furthermore, there are many cases of scientists' causing pain to animals when they do experiments.
http://grammar.ccc.commnet.edu/grammar/gerunds.htm#possessive

4) In their opinion, human life is more important than the life of an animal. There are alternatives to animal testing. Some experiments use computer models and programmes.

5) OK

6) Many animal rights groups break the law to try to stop animal testing. There are even animal rights terrorists who attack research centres and intimidate workers

Here are the additional sentences you requested:

1) However, European law says that animal testing cannot be used for beauty and cleaning products. To find this information, you can do a simple internet search using keywords like "European law animal testing beauty cleaning products." This should direct you to reliable sources such as government websites or reputable news articles that will provide the specific details and regulations regarding animal testing in relation to these types of products.

2) Those who support animal testing say that it is a necessary evil since it helps scientists to develop vaccines as well as new surgical techniques. To understand the perspective of those who support animal testing, you can search for articles, scientific studies, or interviews with experts in the field of medical research or pharmaceutical development. Look for reliable sources that present a balanced view on the topic and consider reading multiple sources to get a comprehensive understanding of their reasons and justifications.

3) Those who oppose animal testing say that it is not always reliable because an animal's response to a drug can be different from a human's. Furthermore, there are many cases of scientists causing pain to animals when they do experiments. To explore the arguments against animal testing, you can conduct a search with keywords such as "arguments against animal testing reliability" or "cases of animal cruelty in scientific experiments." This should lead you to various articles, publications, and studies from animal welfare organizations, ethical discussions, and scientific literature, which will present the concerns and counterarguments related to animal testing.

4) In their opinion, human life is more important than the life of an animal. There are alternatives to animal testing. Some experiments use computer models and programs. If you want to review the viewpoint that human life takes precedence over animal life, you can search for ethical discussions, debates, or opinion pieces on the topic of animal testing. Additionally, to learn more about the alternatives to animal testing, you can search for "alternatives to animal testing in medical research" or "non-animal testing methods." This will provide you with information on the different approaches that scientists and researchers are exploring to reduce or replace animal testing in various areas of study.

5) Human tissue can also be used to test drugs. Other methods include analyzing statistics. To understand the alternatives to animal testing mentioned, search for "human tissue testing in drug development" or "statistical analysis in drug testing." There should be scientific studies, research papers, or articles that discuss the usage of human tissue and statistical analysis as viable alternatives to animal testing. These sources will provide insights into the benefits and limitations of these methods and how they can contribute to the development and testing of drugs.

6) Many animal rights groups break the law to try to stop animal testing. There are even animal rights terrorists who attack research centers and intimidate workers. To explore the actions taken by animal rights groups and the presence of animal rights extremists, you can search for news articles, reports, or studies about animal rights activism and extremism. Reputable news outlets, academic research, or organizations specializing in the study of animal rights should provide you with information about the activities of these groups, any incidents, and the impact they have on the subject of animal testing.