★ 加to的不定詞可用來說明「某人做某事的原因」。
I am going to the market to buy some food.
我要去市場買些食物。
On winter mornings I eat oatmeal to stay warm.
冬天的早晨，我會吃燕麥粥來保持溫暖。
★ 「for + 名詞」也可用來解釋「某人做某事的原因」。
He wants to buy a new suit for his interview.
他想要買套新西裝去參加面試。
She needs to get a second battery for her cell phone.
她需要買一顆手機的備用電池。
★「for + V-ing」則用來表示「東西的用途」。
A fax machine is for sending copies of documents over phone lines.
傳真機是透過電話線，傳送文件的複本。
FTP software is for transferring computer files over networks.
FTP 軟體可以透過電腦網路系統，傳輸電腦裡的檔案。
TIP：for 不能接不定詞。
★ 表達目的時，用「加 to的不定詞」或「for +名詞」的意義相同。
I run every day to get some exercise. = I run every day for exercise.
我每天跑步是為了要運動。
He went to the health club to swim. = He went to the health club for a swim.
他到健身房去游泳。
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※本文節錄自《彩圖初級英文文法Let's See!【四版】（菊8K+解答別冊）》
※延伸閱讀：
[講堂] color和colour
[講堂] garden和yard
[講堂] a.m和p.m
