「３年ぶりのスキーだったんで上手く滑れるか心配だったけど思った以上にまともに滑れたよ」はどのように言えますか？ 自分で考えたのは I was worried if I ski well because I did for the first time in three years, but I did better than I expected. です。こちらの添削もお願いします。
I was worried if I would ski well or not because I was going to do it for the first time in three years, but I did better than I thought.
「思ったより上手・よかった」= to do better than one thought
過去の話に will （未来形) が 推測形の未来となり、would になります。
また、過去の話の中で「三年ぶりにやろうとした」ということは was going to do it for the first time in three years。「やろうとする」 は to be going to do X という形の英文です。
質問者様の英語は多少文法のエラーがありますが、全然理解できますので良いと思います。
僕なら「I was worried whether I could ski well or not」と言います。
「Whether or not」は「〇〇ができるかどうか」になりますので、この「上手く滑れるかどうか」の文書に適用できます。
また質問者様の言いたいことに合わせた英文は以下の通りです：
- I was worried whether I could ski well or not because it was my first time in three years, but I did better than I expected.
I was anxious if I could ski well or not because I had not skied for three years. Yet I could ski more than my expectation.
I was worried whether I could ski well because it has been three years since I had skied last time. But I did a better job than I thought.
be anxious / worry 「心配する」
if /whether ~ (or not) 「〜かどうか」
I had not skied for three years 「3年間スキーをしなかった」
it has been three years since I had skied the last time「前回スキーをしてから3年になる」
また添削ですが、
I was worried if I <could> ski well because I did <had skied> three years ago. But I did better than I expected.
ほとんど問題はなく、十分意図の伝わる文章になっていると思います。
"if" か "whether"の使うときに "or not" は必要ではないです。例えば
"I was worried if I could ski well (or not)."
"I was worried whether I could ski well (or not)."
「３年ぶりのスキーだったんで上手く滑れるか心配だったけど思った以上にまともに滑れたよ」
It had been three years since I last skied, so I was worried whether or not I could ski well. But to my surprise I did better than expected.
「驚いたことに」= to my surprise
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