A “herbologist” is a person who studies plants. The suffix "-ology" means the study of something and "-ologist" means a person who studies something. Similarly, a "zoologist" is a person who studies animals. To further help you, "biology” is a branch of science that studies life; “vigorous” and “fast” are synonyms; “happy” and “well" are also synonyms.

The suffixes "-able" and "-ible" generally mean able to be or able to do, as in the the word “manageable,” which means able to be managed. To solve this analogy, you need to determine which of these answer choices means able to be defended. The correct answer is “defensible."

The suffix "-ten" means to make, so “lengthen” means to make longer and “moisten” means to make wetter.

A “magician” is someone who practices magic, so to solve this analogy, you have to find the word that means someone who studies history, or “historian.” “Magician” and “historian” both have the suffix "-ian," which means type of person. To provide further help, “historiography” is the study of historical practice; a “scientist” is someone who studies science; “humanities” is a broad subject group including history, art, and literature; a “warlock” is a male witch, a wizard. 

The suffix "-ward" means having to do with the direction of [adjective or preposition]. Moving "forward" is the opposite of moving "backward," so you need to pick out an answer choice which represents the opposite of "up." "Down" is the opposite of "up," so "down" is the correct answer.

"Separate" means to divide things or set things or people apart. So, "separate" and "pull apart" are synonyms because they mean the same thing. That means that to solve the analogy, you need to pick out an answer choice that means the same thing as "combine." To "combine" means to put different things together into a single thing. (The prefix "com-" means together.) So, "put together" is the correct answer.

The prefix non- negates the meaning of the word that comes after it, so “nonsense” is opposite in meaning to “sense.” Likewise the prefix un- serves a similar purpose, so someone who is “friendly” is opposite to someone who is “unfriendly.” The key to answering this question is to know which prefix is appropriate to use in this individual case. To provide further help, amiable means friendly and sociable.

The prefix sub- means going under, beneath so a “submarine” is something that travels under water and a “subway” is something that travels underground. The suffix -marine often suggests at a relationship with water.

The prefix non- means related to the number nine. A “nonagon” is a nine-sided shape. To solve this analogy you have to determine which number is related to the prefix hex-, the correct answer is “six.” A “hexagon” has six sides.

“Triplets” are three children born at the same time, of the same mother. The prefix tri- means related to the number three. To solve this analogy, you have to determine what word is used to describe five children born at the same time, of the same mother. The prefix ­-quin means related to the number five, as does the prefix pent-; in this instance, the correct answer is “quintuplets.”