This is not a question. Put it in question form, and maybe I can help you out!
Answer:
Explanation:
This question is too difficult
Answer:
they will kill humans more visiously from humans
Explanation:
The answer should be the first one and the fourth one
While the main idea is usually in the first sentence, the next most common placement is in the last sentence of a paragraph. The author gives supporting information first and then makes the point in the last sentence. Here's a paragraph we can use as an example. Try to locate the topic and the main idea.