They are definitely necessary in terms of preserving normal equilibrium of life in households. For example, cats should hunt for rats and others. Despite the fact that many modern breeds of cats do not have necessary characteristics for that. The great example of such kind of usage of cats is The State Hermitage Museum in St. Petersburg, Russia. Where 70 cats guarded the Museum from rats. You can find more information here - http://www.russianlife.com/blog/hermitage-cats/

But, today in most cases such kind of protection has become unnecessary. Most people buy pets just for fun. It is not complied with even essential conditions for keeping these animals. In the West it is often necessary to obtain permission for the maintenance of animals, in developing countries, unfortunately, pets do not even have passports. Psychological responsibility of their owners, too, is controversial. As an example, I can give the story of one man from a small Kazakh town Kostanai http://www.voxpopuli.kz/en/post/view/id/ 615 (here you can see a photo report about him). He has 50 dogs, but the conditions are terrible. I suppose that some dogs even do not have fundamental food and medical supply. In addition to that, some ill people buy animals to realize their horrible slaughter inclinations. I often see the adverts about dogs and cats without legs or with damaged eyesight. One friend of mine, recently told a story about how he to pick up a kitten. He passed the garbage container and decided to bring a plastic bag into container that someone left near. When he picked it up, he felt that the package move. He opened it and found that there is a little kitten, a few days old. He took him and nursed throughout the night, eventually the kitten survived.

By this two stories, I want to tell that Human Beings very often use pets for their amusement, moreover sometimes with the harm to the animals. Therefore, I think that people can live without pets, however it is uneasy task to prohibit all pets. But the Governmental organizations can issue laws which would oblige people to pass psychological testing in order to determine can this particular person have pets or not.

I understand pros arguments, but I think it is wrong to force somebody to do something, especially something which can caused negative consequences. According to Kant, Mill and other philosophers a person has a right to govern his own body. So, until the child doesn't reached adulthood and can not make decisions for himself - the parents do it for him. I think that in this case both positions for and against vaccination will be correct. But, nevertheless, no one should force another to do even if it is bad for greater good or community. Personal rights should not be sacrifice just because majority want it.

Also, widespread use of vaccines and antibiotics leads to the fact that viruses mutate, develop resistance to antibiotics. Accordingly, such a universal and compulsory vaccination may lead to that in the 21st century will be the second bubonic plague.

Not only vaccines contribute to eradication of smallpox and polio, but also improvement of general living standards, hygiene maintenance, control of water plants, etc.

I think it would work only in combination. In order to know where to go you have to read something about that country. Your enjoy of the country would be greater. For example, when I visited St. Petersburg I didn't think about history very much or great books such as 'Crime and Punishment' by Dostoevsky. But when I realized that I actually was at the same land as great people of the past. It thrilled me more than just being in this city. I really appreciate the words of St. Augustine who also compared traveling with reading: “The world is a book and those who do not travel read only one page.” But, visa versa, who never read about overseas territories never understand fully the pleasure of traveling.

Yes, I think they should.

First of all, when you are a child it easier to learn than when you are an adult. And in this case, the child have better chances to know language fluently. A February 1996 Newsweek article made the claim that "A child taught a second language after the age of 10 or so is unlikely ever to speak it like a native." So, the sooner your child starts learn foreign language the better.

Secondly, I believe that the second language may increase competitiveness in modern world. For example, In 1992 College Entrance Examination Board reported that students who averaged 4 or more years of foreign language study scored higher on the verbal section of the Scholastic Aptitude Test (SAT) than those who had studied 4 or more years in any other subject area. In addition, the average mathematics score for individuals who had taken 4 or more years of foreign language study was identical to the score of those who had studied the same number of years of mathematics.

I don't think that children should be taught more languages than mathematics. But nevertheless, if you know couple of languages, it will help with examination.

Thirdly, the knowledge of second language can help with your native language. For instance with grammar structures and origin of loanwords.

Fourthly, knowing a second language can also give people a competitive advantage in the work force by opening up additional job opportunities. As an example, my friend knows fluently four languages​​: Kazakh, Russian, English and Italian. She works in the field of fashion retail, where it is very important to know different languages ​​to communicate with clients, buyers, colleagues, etc. And when she applied for an internship in a very big luxury company they chose a girl who knows six languages instead of my friend. Maybe only one foreign language is not enough?