文法講座四十六：介係詞 by + Ving/ in + Ving/ on (upon) + Ving
http://www.learnerhall.org/2013/04/by-ving-in-ving-on-upon-ving.html
介係詞後方需加「名詞」，動名詞 Ving 也屬名詞，可放在介係詞後。本單元介紹以下三個意思各不相同的「介係詞 + Ving」組合：
- by + Ving：藉著做…，達成…目標。重點在陳述達成目標的方法。
[例句] 藉著少工作一些，或許可減緩全球暖化。 - In + Ving：在…時；在…過程中。
[例句] 在學英文的過程中，Lisa遭遇過許多挑戰。
In learning English, Lisa faced lots of challenges.
即：When learning English, Lisa faced lots of challenges.
[例句] 做蛋糕時，務必遵照食譜說明，小心結合各項材料。
In baking a cake, you must follow the recipe and assemble the ingredients carefully.
即：When you bake a cake, you must follow the recipe and assemble the ingredients carefully. - on / upon + Ving：一…就…；立即…。
[例句] 一聽到妻子過世的消息，他止不住淚水潰堤。
On hearing the news of his wife’s death, he couldn't hold back the tears.
即：As soon as he heard of his wife’s death, he couldn't hold back the tears.
其中 as soon as 為「連接詞」，後方須接句子，要有主詞 + 動詞。
即：As soon as + S1 + V1, S2 + V2。
[例句] 一到台北，我就會打電話給你。
Upon arriving in Taipei, I will give you a call.
即：As soon as I arrive in Taipei, I will give you a call.
[現在式] [未來式]
as soon as 為「連接詞」，後方須接句子，要有主詞 + 動詞。且連接詞 as soon as 遇到未來時間或未來式時，緊跟在 as soon as 後方的動詞需改用現在式。
[例句] 小女孩一聽到 Psy 的江南 Style，就立刻跳起舞來。
Upon hearing Psy’s Gangnam Style, the little girl started dancing.
即：As soon as the little girl heard Psy’s Gangnam Style, she started dancing. as soon as 為「連接詞」，後方須接句子，要有主詞 + 動詞。且除未來時間外，連接詞 as soon as 左右兩側的動詞時態需對稱，在此 heard 和 started均為過去式。
Global warming can be slowed by working less.即：To slow global warming, we can try working fewer hours.
[目標] [by + Ving 表示達成目標的方法]
[例句] John 試著藉多兼幾份工作來維持收支平衡。
John tries to make ends meet by working several part-time jobs.即：To make ends meet, John works several part-time jobs.
[目標] [by + Ving 表示達成目標的方法]
