Read the passage and decide if the following statements are true (T) or false (F) or not mentioned. (Đọc đoạn văn và quyết định những câu nói đúng (T) hay sai (F) hay không được nói đến (NM).) It is difficult to know how many elephants once lived in the continent, but there may have been at least 3-5 million elephants in Africa in the early part of the twentieth century. People have always hunted elephants for meat, hides and ivory. As the human population grew and weapons became more advanced, elephants were under greater threat. In the late 1970s and early 1980s there was a huge decline in the number of elephants due to the increase in poaching. It is estimated that there are now about 500,000 elephants and they are living in a small number of countries. A ban was given on all international trade in ivory in 1989, and many governments started to give poachers severe punishments. Thanks to such timely actions, some elephant populations, especially those in southern Africa, have recovered over the last decade. However, numerous threats remain for Africa’s elephants. 1. There are now about 3 to 5 million elephants in Africa. 2. Elephants are hunted because they have nowhere to hide. 3. During the late 1970s and early 1980s, the number of elephants decreased sharply. 4. Nowadays, elephants are found only in certain countries in the world. 5. Since 1989, the trade in ivory has been prohibited all over the world.