The word that connects the independent clauses in the sentence is "for."
In the given sentence, "One should make the most of today, for one never knows what tomorrow may bring," the word "for" is a coordinating conjunction that connects the two independent clauses:
"One should make the most of today"
"one never knows what tomorrow may bring"
A coordinating conjunction is a type of conjunction that connects words, phrases, or clauses of equal rank. In this case, "for" is used to show the reason or cause behind the first independent clause. It indicates a cause-and-effect relationship between the two clauses.
Independent Clause 1: "One should make the most of today"
Coordinating Conjunction: "for"
Independent Clause 2: "one never knows what tomorrow may bring"
The use of "for" helps to convey the idea that one should make the most of today because there is uncertainty about what tomorrow may bring. It provides a logical connection between the two ideas and enhances the overall flow and coherence of the sentence.