Answer:
While I would be able to attend the party, I could only arrive after the meal.
Step-by-step explanation:
Subordinate clauses often contain subordinating words at their beginning, used to connect dependent and independent clauses, such as while, when, where, because and more (subordinating conjunctions). On the other hand, it is also possible to include a relative pronoun at their beginning, such as which, that, who, whom etc. In this case, the subordinating conjunction while indicates subordination of the first sentence.