A. in front of the conjugated verb
Swim in the ocean or look at fish
C. construiste is the answer.
There you go.
5: viejo
6: leer
Hope this helped
Spanish/Español:
Ambas civilizaciones practicaron la agricultura, desarrollaron estructuras sociales, levantaron ejércitos y fueron politeístas.
English/Inglés:
Both civilizations practiced agriculture, developed social structures, raised armies, and were polytheists.