Vervet monkeys use vocal alarm calls to warn each other about the presence of predators.
举一反三
- Most modern Loran-C receivers，when not tracking properly，have a（n）（）. A: Bell alarm to warn the user B: Lighted alarm signal to warn the user C: Alternate signal keying system D: View finder for each statio
- According to the passage, most of the students use mobile phones to ______ during the holidays. A: greet each other B: joke with each other C: entertain each other D: chat with each other
- Monkeys ______. A: are left-handed B: can use both hands equally well C: are right-handed D: like to use one hand more than the other
- Confucius believed that ren and li are ________. A: independent of each other B: important concepts about nature C: interconnected with each other D: doctrines about education
- How do Americans call each other in formal situations? A. They normally call each other by their first names. B. They normally call each other by their last names. C. They usually use a title with the last name. D. They usually use a nickname or special name.