Identify the principal clause in the following sentence:
Because the road was flooded, the school bus took the route which runs past the old mill.
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → the school bus took the route
Principal (main) clause:
- The principal (main) clause is the part that is left when the subordinate clauses are taken out. It makes full sense on its own.
- This sentence has two subordinate clauses. “Because the road was flooded” tells why. “Which runs past the old mill” describes “the route”. Take both out. What is left, “the school bus took the route”, is the principal clause.
Why the Other Options are Incorrect?
Option 1: Because the road was flooded — Incorrect. This is an adverb clause of reason. It does not make sense on its own.
Option 2: the school bus took — Incorrect. This is only part of the principal clause. It leaves out “the route”, the object of “took”, so it does not make full sense.
Option 4: which runs past the old mill — Incorrect. This is an adjective clause. It describes “the route” and does not make sense on its own.