People first tamed animals a very long time ago. It was a necessity - they needed to have meat, milk, fur at hand. It was easier to have animals near than to go hunting in dangerous conditions. Then people tamed the next group of animals - to protect the useful animals from the wild. And suddenly humans realized that it was fun to have a home animal. Thus first pets took their place in the homes of our ancestors. Nowadays people can choose a wide range of different pets - cats, dogs, mice, hamsters, snakes, lizards, birds. The most popular are cats and dogs. But I think it is easier to have a caged pet. For example, chinchillas. Because modern people spend most of the time at work, in my opinion it is cruel towards dogs or cats who might feel lonely. But if I speak of myself I would choose a dog, because it is a loyal and kind creation and I like long walks where my dog would be a companion.
2. He wrote (past simp - to write) this book in response to the Great Depression of the 1930s.
3. Keynes was (past simp - to be) a British economist.
4. Keynes's work aroused (past simp - to arouse) Frank P. Ramsey to outline his own "subjective" theory of probability.
5. Keynesian economics is (pres simp - to be) the opposite of laissez-faire economics.