Expressa o que estava acontecendo num ponto do passado ou uma ação em andamento quando outra aconteceu. É formado pelas formas verbais do verbo to be no passado (was/were) mais verbo principal acrescido de –ing:

What were you doing at 6 o’clock yesterday?

You were doing your lesson when I called,

As the man was looking at the picture, the thief stole his wallet.

Também pode expressar duas ações que ocorriam simultaneamente:

While Barbara was swimming, I was playing soccer.

Só meu

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