how do i make one sentence subordinate to the other.
sentence: People know they are going to have to retire. They often don't save enough money to do so comfortably.
is this correct?: although people know they are going to have to retire, they often don't save enough money to do so comfortably.
Yes, that's right. Using "although" as a subordinating conjunction is one of the main ways to do this.
Here's a webpage with a list of the primary subordinating conjunctions:
http://www.chompchomp.com/terms/subordinateconjunction.htm
Yes, your sentence is correct! You have successfully made the second sentence subordinate to the first sentence by using the subordinating conjunction "although." This conjunction helps to show the contrast or the opposition between the two ideas. Here is the breakdown:
Original sentence: People know they are going to have to retire. They often don't save enough money to do so comfortably.
Subordinated sentence: Although people know they are going to have to retire, they often don't save enough money to do so comfortably.
In the subordinated sentence, the conjunction "although" makes the first part of the sentence ("people know they are going to have to retire") the main clause, and the second part ("they often don't save enough money to do so comfortably") becomes the subordinate clause, which provides additional information or presents a contrasting idea.