I wonder if that battle was necessary. Wasn't there another way to solve their differences and avoid losing all those lives?
I wonder if they really had to fight. Couldn't they have worked things out without killing so many people?
ーI wonder if that battle was necessary. Wasn't there another way to solve their differences and avoid losing all those lives?
「その戦は必要だったのかな？たくさんの命を失わずに争いを解決する他の方法はなかったのかな？」
battle で「戦」
solve their differences で「彼らの争い・不和を解決する」
lose all those lives で「たくさんの命を失う・落とす」
ーI wonder if they really had to fight. Couldn't they have worked things out without killing so many people?
「本当に戦わなければいけなかったのかな？多くの人を殺さず、解決できなかったのかな？」
fight は動詞だと「戦う」、名詞だと「戦い」という意味です。
work out は「問題の解決策を見つける・解決する」
ご参考まで！
カナダ 
