A forma ativa dos verbos é a que estamos acostumados a usar na língua inglesa até agora, em que o sujeito executa a ação, portanto a frase mostra o que o sujeito está fazendo:

Ex.: John plays the piano. (Está claro quem pratica a ação).

A forma passiva mostra o que acontece com o objeto.

The piano is played. (O fato de importância é o que acontece ao piano, e não quem o toca).

A forma passiva será usada quando o que ocorre com o objeto for mais importante ou quando o sujeito não for importante ou for desconhecido.

Ex.: We were robbed on that street. (Não se sabe quem nos assaltou).
América was discovered in 1492. (Queremos ressaltar o descobrimento e não quem descobriu).

FORMA

A forma passiva muda de acordo com o tempo verbal usado na frase de origem, mas o verbo to be sempre será o auxiliar, que será colocado no tempo verbal original seguido do past participle.

Tempo verbal da sentença original	Forma Passiva	Exemplo
Simple Present	Am/is/are + past participle	Gorillas inhabit is jungle. à This jungle is inhabited by gorillas
Present Continuous	Am being/is being/ are being + past participle	Sorry, but we are remodelling the airport à Sorry, but the airport is being remodelled.
Simple Past	Was/were + past participle	They didn’t hear me, so I escaped. à I wasn’t heard, so I escaped.
Past Continuous	Was being/ were being + past participle	Someone was playing the violin. à The violin was being played.
Present Perfect	Have been/ has been/ + past participle	The virus has already attacked this country. à This country has already been attacked by the virus.
Past Perfect	Had been + past participle	I realized that they had hit me on purpose. à I realized that I had been hit on purpose.
Will – Future	Will be + past participle	Someone will rob you if you go there. à You will be robbed if you go there.
Going to – Future	Am/is/are going to be + past participle	They are going to build a bridge here. à A bridge is going to be built here.