Fill in the blank with a suitable pronoun:
Mr. Kim is our professor. _______ teaches us Philosophy.
The subject pronouns can be divided into two general categories – Personal and impersonal pronouns. A personal pronoun is a pronoun that is associated with a particular person, like ‘he’, ‘she’ and ‘they’. While an impersonal pronoun is commonly used to speak about inanimate objects/things. 'It’ is an impersonal pronoun that is used for this purpose. Since the subject of the sentence is a person, ‘it’ cannot be used. Thus option A is incorrect. Further, under personal pronoun, we use ‘he’ for third-person singular, ‘they’ for third person plural and ‘we’ for first person plural. As the sentence speaks about ‘Mr. Kim’ in the third person and since it is just one person, we must use ‘he’. Thus option B is correct, while options C and D are incorrect.