Explanation
Use "before" and "after" to show which event happens first. You can use them before a noun, like "before dinner," or before a full clause, like "after I finish work."
In "After I finish work, I will call you," "after" shows the first event in time. "I finish work" is the time clause, so it uses present simple, not "will finish." "I will call you" is the main sentence, and it happens later. Japanese often uses "〜の前に" and "〜のあとで," so the meaning is similar, but English keeps the time clause in a simple form.
「before」「after」は、どちらの出来事が先かを表します。名詞の前にも使えますし、"after I finish work" のように節の前にも使えます。
たとえば "After I finish work, I will call you." では、"after" が「仕事が終わったあと」を表します。"I finish work" は時間を表す節なので、未来のことでも "will finish" にしません。"I will call you" が本体の文で、そのあとに起こることです。日本語の「〜の前に」「〜のあとで」に近いですが、英語では時間を表す節の中は現在形にします。
Examples
- I wash my hands before dinner. 私は夕食の前に手を洗います。
- After school, I play soccer with my friends. 放課後、友だちとサッカーをします。
- Before you leave, please turn off the lights. 出る前に、電気を消してください。
- Can I call you after work? 仕事のあとで電話してもいいですか。
- She did her homework after she got home. 彼女は家に帰ってから宿題をしました。
- Don't eat anything before you see the doctor. お医者さんに会う前は、何も食べないでください。
Common Mistakes
Japanese learners often use "will" in the time clause.
Wrong: "After I will finish work, I will call you."
Right: "After I finish work, I will call you."
Use present simple after "before" and "after" when the clause talks about the future.
日本語話者は、時間を表す節の中でも "will" を使ってしまいがちです。
誤り: "After I will finish work, I will call you."
正しくは "After I finish work, I will call you."
未来のことでも、"before" や "after" の後ろの節は現在形にします。