多久了:for / since 與完成式

🎯 這一課你會學會

精準講「做了多久」——用 for(一段時間)和 since(從某個時間點)。這兩個小字配完成式超常用,分清楚就不會錯。

💬 先聽一段對話

Mia: How long have you known Jun?（你認識 Jun 多久了?)
Rin: I've known him for about ten years. Since high school.（大概十年了。從高中開始。)
Mia: Wow, that's a long time!（哇,很久了!)
Rin: Yeah. We've been friends since we were fifteen.（對啊。我們從十五歲就是朋友。)

🔑 關鍵句型

• for + 一段時間(長度)：for two hours / for three years / for a long time.
• since + 時間點(起點)：since 2019 / since Monday / since I was young.
• How long have you + 過去分詞/been V-ing?　→ 用 for / since 回答。

🧩 文法點:for vs since

① for = 「持續多久」(一段時間的長度):

• for two days、for five minutes、for ages、for a week。
• I've lived here for five years.（住了五年——長度)

② since = 「從哪個時間點開始」到現在:

• since Monday、since 2020、since this morning、since I met you。
• I've lived here since 2019.（從 2019 到現在——起點)

③ 兩個都配「完成式」(講從過去延續到現在):

• I've worked here for three years. = I've worked here since 2021.（同一件事,兩種角度)
• 也可配現在完成進行:I've been waiting for an hour / since noon.

④ since 後面還能接「一個過去的句子」:

• I haven't seen her since she moved to Canada.（自從她搬去加拿大——接子句,用過去式)

判斷小訣竅:後面是「一段長度」→ for;後面是「一個時間點/起點」→ since。

📒 高頻單字

單字	KK 音標	中譯	例句
since	/sɪns/	自從	since 2020（從2020起)
ago	/əˈɡo/	之前	two years ago（兩年前)
for ages	/fɔr ˈedʒɪz/	很久	I've waited for ages.（我等好久了。)
whole	/hol/	整個	the whole week（一整週)
almost	/ˈɔlmost/	幾乎	almost ten years（快十年)

🗣️ 發音提醒

• since /sɪns/:結尾 -nce = /ns/,別漏 s。
• for 常弱讀成 /fɚ/:「for two years」→ 「fə-two-years」。
• ages /ˈedʒɪz/:「AY-jiz」,for ages 是「很久」的口語。

✍️ 開口練習

練習 1:for 還是 since?

• ＿ three years（長度)→ for
• ＿ last Monday（時間點)→ since
• ＿ I was a child（過去起點)→ since
• ＿ two weeks（長度)→ for

練習 2:回答 How long。

How long have you ＿? — I've ＿ for ＿ / since ＿.

練習 3:講兩件事,一個用 for、一個用 since。

I've lived in ＿ for ＿. I've studied English since ＿.

🎒 帶走

• for + 一段長度(for two years)、since + 一個起點(since 2020)。
• 兩者都配完成式,講「從過去延續到現在」。
• since 後面也能接一個過去的句子(since she left)。

下一課,把時間再往前推:過去完成式——講「過去的過去」,說故事排順序。