The prefix "infra-" generally means below or under, so the word “infrastructure” means basic structure or "foundation." To provide further help, a “trial” is a test; a “variable” is something that can change; a “luminary” is a famous or successful person. 

The prefix "an-" means toward, to join, or to add onto. The word “annex,” when used as a verb, means add or join, and it is most commonly used when talking about adding territory to an existing defined area of land , as in “In the twentieth Century the United States annexed the islands of Hawaii.” The best answer, therefore, is “add.” None of the other answer choices are close in meaning to "annex": “accommodate” is  verb that means provide someone with a house or help by making changes to the way in which one regularly does something; "sing" means audibly perform a song; and "sort" means categorize or physically arrange into categories.

The prefix "a-" means not, so “atypical” has the opposite meaning of “typical.” Something that is “typical” is predictable, boring, or common, so “atypical” is closest in meaning to “uncommon.” The prefix "un-" functions here in the same way as the prefix "a-" does in "atypical"; it negates the meaning of the word. As for the other answer choices, “zealous” means passionate; “derogatory” means disrespectful, rude, or offensive; “wary” means cautious, anxious, or careful; and "traitorous" means treacherous or betraying the trust of someone or a group.

The prefix "ex-" means out or away, so to “exhale” means to breathe out, just like to “inhale” means to breathe in. That makes "breathe" the closest synonym to "exhale" amongst the answer choices. As for the other answer choices, "whine" means moan or complain about something.

The prefix "dis-" means apart or away, so the word “distant” means located far away or difficult to read the emotions of and "faraway" is the correct answer. To provide further help, “nearby” is an antonym of "far-away” and means located close by; “erroneous” means incorrect or made-up; “discomfiting” means causing you to feel uncomfortable; and “abhorrent” means disgusting or disgraceful. 

The prefix "re-" means again or in additional to. A “recourse” is a different option, or an alternative, so "alternative" is the correct answer. To provide further help, an “introduction” is something that begins something and a “conclusion” is something that ends something, "normality” means ordinariness,  and "text" is written words or a collection of written words such as a poem or book.

The root "fer" means to bring or to carry, as in how “ferries” move passengers from one side of a body of water or river to another. Similarly, the word “referral” means the bringing of a source that offers help or information. It is closest in meaning to the word “recommendation.” To provide further help, “gratis” means free; “criterion” means the principle or decisive factor for picking or evaluating something; a “dictator” is a leader who rules through absolute power and control; and a “representative” is someone elected to represent the peoples’ interests.

"Dishonest" means not honest or untrustworthy.

"Subterranean" means underground: It contains the prefix ­"sub-," which means under or below, and the root "terra," which comes from the Latin word for earth. So, "underground" is the best answer, because it is closest in meaning to "subterranean."

"Abnormal" is defined as unusual or not normal. "Atypical" is defined is not typical, so "atypical" is the best answer choice. The prefixes "a-" or "ab-" can mean not, as is demonstrated in "abnormal" and "atypical" respectively meaning not normal and not typical.