ご質問どうもありがとうございます。
様々な表現があると思いますが、いくつか自然な表現を紹介します。
--- 英語なら、この文脈では副詞構造より（最後に=recently）、形容詞(recent, last)を使うほうが自然というような気がします。
1. The most recent movie I saw was _____.
私が最後に見た映画は◯◯です
2. The last movie I saw was_____.
私が最後に見た映画は◯◯です
ちなみにアメリカ英語では movie がよく使われますが、イギリス英語では film もよく使用されます。
お好みに合わせて使い分けてみてください。
ご参考にしていただければ幸いです。
The last movie I saw in the theater was ___________
The last movie I saw was ______________ or The last movie I watched was _________________
This expression works well if you are talking about a movie you saw in the theater, at home, on a plane, etc.
To be more specific you could say you saw the movie in the theater,
The last movie I saw in the theater was ___________
"The last movie I saw was ______________" あるいは "The last movie I watched was _________________"（最後に見た映画は～でした）
この表現は映画館、家、飛行機などで見た映画について使うことができます。
より具体的に、「映画館で見た」と伝えることもできます。
The last movie I saw in the theater was ___________（最後に映画館で見た映画は～でした）
"The last movie I saw was..." Is a common term, you can replace "saw" with "watched" as both used in the past tense, of the previous films that you had seen.
"The last movie I saw was..."（最後に見た映画は...でした）は一般的な言い方です。"saw" を "watched" と置き換えることもできます。どちらも過去形です、過去に見た映画について言います。
The last' speaks of the most recent event, in this case, what was watched recently.
All these sentences explain that the most recent movie watched was (insert name).
Saw, have seen and watched are all the past tense of 'see'.
The last' は最近の出来事を指します。この場合は「最近見たもの」です。
これらどの文も、最後に見た映画が何かを伝えています。
"Saw" "Have seen" "Watched" これらは全て 'See'（見る）の過去時制です。
This is a simple, complete, and formal way to state what the last movie that you watched was. This is easily understandable in all dialects of English. I hope that this helps! :)
Have you seen the movie, "Wolf?" I just watched it the other day.
Oh you should see the movie, "Wolf", I saw it yesterday.
I haven't seen any movies since I watched, "Wolf".
Have you seen the movie, "Wolf?" I just watched it the other day.
Oh you should see the movie, "Wolf", I saw it yesterday.
I haven't seen any movies since I watched, "Wolf".
The movie called, "Wolf" is the last one I have seen.
Have you seen any good movies lately? The last one I saw was called, "Wolf".
Have you seen the movie, "Wolf?" I just watched it the other day.（「ウルフ」っていう映画は見ましたか。私はこの間見ました）
Oh you should see the movie, "Wolf", I saw it yesterday.（「ウルフ」っていう映画は見た方がいいよ。私は昨日見ました）
I haven't seen any movies since I watched, "Wolf".（「ウルフ」を見てから他の映画は見ていません）
The movie called, "Wolf" is the last one I have seen.（最後に見た映画は「ウルフ」です）
Have you seen any good movies lately? The last one I saw was called, "Wolf".（最近何か面白い映画を見ましたか。私が最後に見たのは「ウルフ」という映画です）
1. The last movie I saw was ___.
By saying 'The last movie', you are referring to the movie you have watched most recently. 'Saw' is a verb that means you have looked at something. In this case, you looked at a movie (which is a noun). It is also a synonym of 'watched'. So, by saying 'The last movie I saw was' you are talking about a movie you watched recently.
2. 'The last film I saw ___.'
This means exactly the same thing as the first sentence. 'Film' is another word for 'movie'. This means it is a synonym.
1. The last movie I saw was ___.（私が最後に見た映画は）
'The last movie' は最近見た映画を指します。'Saw' は「見た」という意味の動詞です。ここでは 'Movie'（名詞）を見たわけです。'Saw' は 'Watched' の同義語です。ですから、'The last movie I saw was' は最近見た映画について言います。
2. 'The last film I saw ___.'（私が最後に見た映画は）
これは上の文と全く同じ意味です。'Film' は 'Movie'（映画）の別の言い方、つまり同義語です。
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