1. The basic instinct of survival drives all living organisms.
生存的基本本能驱使着所有的生物。
2. The survival of the fittest is a principle in the natural world.
适者生存是自然界的一个原则。
3. He endured many hardships, but his strong will to survive kept him going.
他忍受了很多艰难，但是他强烈的求生意志让他坚持下去。