A person who can speak and understand many foreign languages is best described by which term?

Introduction / Context:
Language related vocabulary is a common topic in general English and general knowledge sections. There are several different terms that describe people who have particular skills or professions in language, such as linguist, grammarian, bilingual person, and polyglot. This question asks for the specific term used for someone who knows and can use many foreign languages, which is an important distinction for vocabulary based questions.

Given Data / Assumptions:

• The person described knows many foreign languages, not just two.
• The options include grammarian, polyglot, linguist, and bilingual.
• We assume standard English usage as found in dictionaries and exam preparation materials.

Concept / Approach:
A polyglot is defined as a person who can speak and understand several languages fluently. The key idea is the number many, usually more than two or three. A bilingual person speaks two languages. A linguist is someone who studies language scientifically, including its structure, history, and use, but may not necessarily speak many foreign languages. A grammarian is an expert in grammar rules and analysis, again not necessarily someone who speaks multiple languages. Therefore, when the emphasis is on knowing many foreign languages, the most accurate term is polyglot.

Step-by-Step Solution:
1. Focus on the phrase knows many foreign languages in the question stem.2. Recognize that bilingual refers specifically to someone fluent in two languages.3. Understand that a linguist studies language as an academic field and may specialize in one or several languages but is not defined by the number of languages spoken.4. A grammarian is an expert in grammatical rules and structures, which may apply to one or more languages, but again the term does not directly mean many languages spoken.5. The word polyglot is formed from Greek roots meaning many tongues or many languages, directly matching the idea of someone who knows several languages.6. Therefore, the correct answer is polyglot.

Verification / Alternative check:
Dictionaries define polyglot as a person who knows and is able to use several languages. Biographical articles about famous language learners often use the term polyglot to describe people who speak five, ten, or even more languages. In contrast, bilingual is used in discussions of education or communities where two languages are used, such as bilingual schools or bilingual children. Linguistics textbooks define linguist as a student or scholar of linguistics rather than simply a language learner. These definitions support the choice of polyglot for the person described in the question.

Why Other Options Are Wrong:
Option A, grammarian, is incorrect because it refers to someone who specializes in grammar, not necessarily in speaking many languages. Option C, linguist, is wrong in this context because it emphasises academic study of language, not proficiency in many foreign languages. Option D, bilingual, is also incorrect because it describes someone who knows two languages, whereas the question specifies many languages. Therefore, only polyglot directly captures the meaning required.

Common Pitfalls:
Students sometimes assume that a linguist must automatically be fluent in many languages, but many linguists focus on the structure or history of one or a few languages. Another pitfall is to confuse bilingual and polyglot, forgetting that bi means two while poly means many. A simple way to avoid this confusion is to pay attention to the numerical prefixes, especially since they appear in many other terms such as bicycle or polygon.

Final Answer:
A person who knows and can use many foreign languages is best described as a polyglot.