Turn into passive voice: I had finished my homework before I went to bed.

Để chuyển câu "I had finished my homework before I went to bed" sang dạng bị động, chúng ta cần chuyển động từ "finished" thành dạng bị động, và chuyển thì của động từ thành quá khứ hoàn thành trong câu.

Cách 1: My homework had been finished before I went to bed.

Cách 2: Before I went to bed, my homework had been finished.

Cách 3: By the time I went to bed, my homework had been finished.

Before going to bed, my homework had already been finished by me.

The homework was finished by me before I went to bed.

Before I went to bed, my homework had been finished.

My homework had been finished before I went to bed.