Question

Leia o texto e responda: *
The verb tenses “have speculated” (ref. 4), “have determined” (ref. 5) and “have known” (ref. 6) are:
The verb tenses “have speculated” (ref. 4), “have determined” (ref. 5) and “have known” (ref. 6) are:
Future
Simple present
Present perfect
Past Simple

Answer 1

as frases estão no tempo verbal PRESENT PERFECT, porque têm sua composição como:

HAVE + VERBO NO PARTICÍPIO