The watchman switched on the lights before it began to grow dark.

A. The lights were only switched on before it began to grow dark.
B. The lights are being switched on before it began to grow dark.
C. The lights were being switched on by the watchman before it began to grow dark.
D. The lights were switched on by the watchman before it began to grow dark.
✅ The correct answer is option D.

The doctor advised the patient not to eat rice.

A. The patient was advised by the doctor not to eat rice.
B. The patient was advised by the doctor that he should not eat rice.
C. The patient was being advised by the doctor that he should not rice by the doctor.
D. The patient has been advised not to eat rice by the doctor.
✅ The correct answer is option A.