In English grammar, the phrase “each of them” is what is known as a distributive pronoun. This means that it refers to each individual member of a group separately, rather than the group as a whole.
When it comes to the verb agreement with “each of them,” the verb should agree with the number of the individual member that the pronoun refers to, rather than the collective noun as a whole.
For example, if you say “Each of the students has a textbook,” the verb “has” agrees with “each,” which is singular. Similarly, if you say “Each of the books has been read,” the verb “has been” agrees with “each,” which is also singular.
On the other hand, if the individual members referred to by “each of them” are plural, the verb should be plural as well. For example, if you say “Each of the students have their own interests,” the verb “have” agrees with “students,” which is plural.
Therefore, the correct usage would be “each of them has” if the individual members are singular, and “each of them have” if the individual members are plural.
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