Meaning: 'This' is used to refer to something that is close in time or space, in this case, the topic of language learning.

Wrong options:

• than: The word 'than' is a conjunction used for comparisons, which does not fit the context of introducing a topic.
• there: 'There' is an adverb indicating a place or existence, which does not appropriately introduce a topic.
• whom: 'Whom' is a pronoun used for the object of a verb or preposition, which does not fit as a subject in this context.
• who: 'Who' is a pronoun used for the subject of a verb, but it does not serve to introduce a topic.
• doubt: 'Doubt' is a noun that refers to uncertainty, which does not fit the grammatical structure needed here.
• process: 'Process' is a noun that refers to a series of actions, but it does not serve to introduce the topic.

Correct answer: process

Explanation: The term 'process' is a noun that refers to a series of actions or steps taken to achieve a particular end. It fits grammatically as it serves as the subject of the sentence, describing the act of learning a language.

Meaning: 'Process' refers to a method or series of actions taken to achieve a particular result, in this case, learning a language.

Wrong options:

• than: 'Than' is a conjunction used for comparisons, which does not fit as a subject in this context.
• this: 'This' is a demonstrative pronoun that does not serve as a noun in this context.
• there: 'There' is an adverb indicating a place or existence, which does not fit as a subject.
• whom: 'Whom' is a pronoun used for the object of a verb or preposition, which does not fit as a subject here.
• who: 'Who' is a pronoun that does not serve as a noun and cannot describe the act of learning.
• doubt: 'Doubt' is a noun that refers to uncertainty, which does not fit the context of describing the act of learning.

Correct answer: who

Explanation: The word 'who' is a relative pronoun that refers to people and is used to introduce a clause. It fits grammatically as it connects the subject 'people' to the action of putting in effort, maintaining clarity in the sentence structure.

Meaning: 'Who' is used to refer to the subject of a verb, in this case, the people who are learning languages.

Wrong options:

• than: 'Than' is a conjunction used for comparisons, which does not fit in this context.
• this: 'This' is a demonstrative pronoun that does not refer to people and cannot serve as a subject.
• there: 'There' is an adverb indicating a place or existence, which does not fit as a subject in this context.
• whom: 'Whom' is a pronoun used for the object of a verb or preposition, which does not fit as a subject here.
• doubt: 'Doubt' is a noun that refers to uncertainty, which does not fit the grammatical structure needed here.
• process: 'Process' is a noun that does not refer to people and cannot serve as a subject.

Correct answer: doubt

Explanation: The word 'doubt' is a noun that refers to uncertainty. It fits grammatically as it serves as the object of the preposition 'beyond,' indicating that there is no uncertainty regarding the necessity of speaking multiple languages.

Meaning: 'Doubt' refers to a feeling of uncertainty or lack of conviction, in this case, indicating that there is no uncertainty about the necessity of language skills.

Wrong options:

• than: 'Than' is a conjunction used for comparisons, which does not fit in this context.
• this: 'This' is a demonstrative pronoun that does not fit as an object of a preposition.
• there: 'There' is an adverb indicating a place or existence, which does not fit as an object in this context.
• whom: 'Whom' is a pronoun used for the object of a verb or preposition, which does not fit as an object of 'beyond.'
• who: 'Who' is a pronoun that does not fit as an object and cannot serve in this context.
• process: 'Process' is a noun that refers to a series of actions, which does not fit the grammatical structure needed here.