It’s just a matter of order.
In an active sentence, the **SUBJECT** (somebody/thing doing something) comes before the *VERB* (what they’re doing). (“**John** *threw* the ball.”)
In a passive sentence, the *VERB* goes first and the **SUBJECT** either follows (“A ball *was thrown* by **John**”) or is excluded (“A ball *was thrown*.”)
Usually the active voice is better because it’s generally shorter and stronger, but there are some exceptions like being polite or when you care more about the OBJECT (the receiver of action), i.e. “I’ve been shot!”
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