「if + 主語 + were to + 原形動詞」は全く実現不可能な仮定から、実現の可能性のある仮定まで、未来についての仮定を表します。主語が1人称・3人称の場合には were to の代わりに was to を使うこともあります。仮定法過去の1種なので、帰結節の動詞は「過去形助動詞(would、should、could、might)＋原形」となります。
If I were to be reborn, I would like to be a bird.
もし生まれ変わることができるなら、私は鳥になりたい。
If he were to fail, he would try again.
万一失敗すれば、彼はまたやるだろう。
She would help us if I were to ask her.
頼めば彼女は私たちを助けてくれるでしょう。
If I were to tell you, you would be astounded.
もしきみに話してあげたら、きみはびっくりするだろう。
What would you do if war were to break out?
万一戦争が起こるとしたらどうなさいますか。
If the Pacific Ocean were to dry up, he would never change his way of thinking.
太平洋が干上がるようなことがあっても、彼は考え方を変えないだろう。
If the children were to go to the seaside, they would be happy.
海へ行くのなら、子どもたちは喜ぶだろう。
If the sun were to go out, all living things would die.
もし太陽が消滅したら、生物はみな死ぬだろう。
If we were to live on the moon, we could enjoy viewing the earth.
もし月で暮らすようなことになれば、地球の眺めを楽しめるだろう。
If the sun were to rise in the west, she wouldn't change her mind.
万一太陽が西から昇るようなことがあっても、彼女は決心を変えないだろう。
If you were to live on a desert island for a year, what would you bring with you?
もし1年間、無人島に住むようなことがあれば、何を持って行きますか。
They all should be delighted if they were to go to the beach tomorrow.
もし明日海に行くことでもあれば、彼らはみんな喜ぶだろうに。
If you were to die tomorrow, what would you eat for your last meal?
もし明日死ぬことになったら、最後の食事に何を食べますか。
If all the Antarctic ice were to melt, the level of the seas would rise to drown most of the seaports.
仮に南極大陸の氷が全部溶けるようなことがあれば、海の水位が上がってしまって、大部分の港は水没してしまうだろう。