The border between two countries is also called the “frontier.” The words “border” and “frontier” both describe the place where one country ends and another begins. An “estuary” is the place where a river empties out into the ocean; “gloom” is a feeling of great sadness and lack of hope; “hardship” is some difficulty in your life, like being very hungry all the time; and an "arc" is a curved line.

The context of the second part of the sentence tells us that the underlined word must be a word that means the state of living without much money and being poor. This means the correct answer is “poverty.” “Poverty” is the opposite of “affluence.” “Affluence” means the state of living with lots of money. A “community” is a group of people who live together or near each other; and “protection” means defense against something.

Given the context of this sentence, it is clear that the principal makes welcoming remarks for the school year. She is kicking off the beginning, or the commencement, of the school year. A commencement is the beginning or start of something. 

The author of this sentence is describing the point at which a river begins up in the mountains. Another word for where something begins or the thing that produces something is its “source.” The word “summit” means top of the mountain; this may have been a confusing option for this question, but it is not the correct answer. “Terrain” means land, and this makes sense, as the root "terra" means earth or land.

The zoos want to make their animals' habitats more closely match the areas in which they would live in the wild. The word “habitat” is used to describe the home where an animal lives in the wild, so one might accurately say that “a bear’s habitat is the forest" and "habitat" is the correct answer. A “hovel” is the name of a very small and filthy house or a shack; and “mistrust” means suspicion. (The prefix "mis-" usually means not, like in the words “misunderstand,” “mistrust,” or “misplace.”) Animals in the zoo get food and toys, but adding "plants and landscape features" to an exhibit has nothing to do with toys or food.

The volume was loud, and therefore the police told them to turn off the music and not disturb the neighbors.

This sentence conveys that while Renee seemed to understand the material from math class, she actually didn't. You thus need to pick out a noun that means something like "feeling." The answer choice that best fits this requirement is "impression," which means feeling based on initial assumptions but no proof or further investigation. None of the other answer choices make sense in the blank.

If you hear a loud noise, you might look for the noise's source without thinking about it, so we need to pick out an answer choice that means something like "an action done without thinking." "Reflex" has this meaning exactly, so it is the correct answer. As for the other answer choices, none make sense in the sentence's blank: "incentive" means reward; "behavior" means conduct or pattern of actions; and "stimulus" means something that causes something else to happen.

From the context, you know that the correct answer must be somewhere where apples grow; this should lead you to the correct answer, which is “orchard.” An “orchard” is somewhere, usually on a farm, where fruit grows in trees. A “university” is an institution like a college where people study after high school; a “convent” is a religious building where nuns live.

From context, it sounds like the hurricane was a very bad thing for the community; this means that the correct answer is “disaster.” A “disaster” is a terrible thing that happens, like a hurricane or a flood. A “portion” is a specific amount of something given to someone. An “appeal” is an act of ask for something or for someone’s help.