Subordinators are words that help to connect two clauses by making one of them dependent on the other in terms of meaning. These connectors are essential in forming complex sentences in English language. Some common subordinators include "because, although, since, unless, when, until" among others. There are various synonyms for subordinators that serve the same purpose in sentence construction such as "conjunctions, connectors, joiners, linkers, conjunction phrases" among others. These words help to link phrases or clauses without disrupting the flow of the sentence while indicating the relationship between the dependent and independent clauses. Overall, subordinators and their synonyms are essential in improving the complexity and structure of sentences in English language.