Question

He was writing a book. / a book. By him. * a. Was written b. Had written

Answer 1

A alternativa para a Voz Passiva  é: A book was being written by him.

Active voice

O sujeito pratica a ação do verbo.

Exemplos:

John studies Math.

My mother cooks dinner.

I am going to watch TV now.

Passive voice

O objeto  será o sujeito.

Exemplos:

The car is being washed by my father.

A cake is made by Jennifer.

Observação: A frase do exercício está no  ''past continuous'' = was writing, por isso a voz passiva   tem que ser ''was being written''

He was writing a book.

Ele estava escrevendo um livro.

A book was being written by him.

Um livro estava sendo escrito por ele.

Entenda mais sobre Voz passiva em:

brainly.com.br/tarefa/40555072

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