I met a colleague with whom I am writing a report in the lift. – В лифте я встретил коллегу, с которым пишу отчет. After all, we must remember for whom we are catering. – В конце концов, мы должны помнить, для кого готовим. Whose
2. the person or persons that, or a person that: used to introduce a relative clause. the man who came to dinner. 3. any person or persons that; whoever. used as an indefinite relative with an implied antecedent. who steals my purse steals trash”.
I'm living in a country whose language I have been learning for less than 5 months. If the sentence must be formulated without whose, I think it would be grammatical to use one of the following structures: I'm living in a country the language of which I have been learning for less than 5 months.

Another pronoun which could replace it is whom: We use whom in formal styles or in writing to refer to people when the person is the object of the verb (of the relative clause). We use that instead of who, whom or which in relative clauses to refer to people, animals and things. That can act as the subject or the object of the relative clause:

Who is the subject pronoun, and it has its object form whom and possessive form whose. Who and whom refer to people only. For the last half century or so who has been used more and more for both positions: subject and object. Whom, on the other hand, is used as an object or as the complement of a preposition in formal contexts. . 329 31 260 10 54 329 440 211

whom whose who usage