Respuesta :
The only sentence which is in the active, and not the passive voice, is the third sentence - Membership in the group declined after the war ended.
The active sentence is
→ Membership in the group declined after the war ended.
This sentence uses simple past tense
✐ formula past simple
(+) S + Verb 2 + O/C
(-) S + did + not + Verb 1 + O/C
(?) Did + S + Verb 1 + O/C?
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Subject : English
Keywords : Active Voice, Past simple
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