You are provided with two sentences. Combine them into one sentence with a dependent clause.
He bought a new car. It was expensive.
He bought a new car, which was expensive.
Complete the following task based on the instruction and optional input provided.### Instruction:
You are provided with two sentences. Combine them into one sentence with a dependent clause.

### Input:
He bought a new car. It was expensive.

### Output:
He bought a new car, which was expensive.