Which sentence is true about idioms? A. Idioms are examples of words used in a very plain way.

B. You can't change words around in an idiom and have it mean the same thing.

C. Idioms are easy to explain to people who speak a different language from you.

D. You can't use an idiom to describe a situation that might happen today.

Read the excerpt from “the railroad earth.” o well anyway i'll be learning eventually to like the railroad and sherman will like me some day, and anyway another day another dollar. the narrator of this excerpt can best be described as friendly.optimistic.wealthy.intelligent.

(1) fire extended humans’ geographical boundaries by allowing them to travel into regions that were previously too cold to explore. (2) it also kept predators away, allowing early humans to sleep securely. (3) fire, in fact, has been a significant factor in human development and progress in many ways. (4) other obvious benefits of fire are its uses in cooking and in hunting. (5) probably even more important, however, is that learning to control fire allowed people to change the very rhythm of their lives. (6) before fire, the human daily cycle coincided with the rising and setting of the sun. (7) with fire, though, humans gained time to think and talk about the day’s events and to prepare strategies for coping with tomorrow. the sentence that expresses the main idea is: (type the number of the sentence. then click “go.”)

Compare: what are the similarities and differences between "artificial flavors" and "natural flavors"? why does schlosser explain these two terms in such detail?