Question

What is the structure of the Present Perfect tense?

"The Earth's climate has changed before..."
"...modern society has e ver seen before."


a) auxiliary verb (have/has) + main verb (Past Simple)
b) auxiliary verb (have/has) + main verb (Past Participle)

Qual é a resposta certa?
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Answer 1

Nesse caso é a letra B, dá para perceber tmbm pelo seen que é past participle, se fosse past simple seria saw...