Defining relative clauses such as these specify which noun we are talking about.
像这些句子就是限定性定语从句了，限定了我们所讨论的名词是哪个。
英语百科
Relative clause
A relative clause is a kind of subordinate clause that contains an element whose interpretation is provided by an antecedent on which the subordinate clause is grammatically dependent; that is, there is an anaphoric relation between the relativized element in the relative clause, and the antecedent on which it depends.