學術英文的句型Sentence Patterns in Academic English

名詞化：把動作變成「概念」

日常英文用動詞說「誰做了什麼」：The government decided to raise taxes.。學術英文常把動詞、形容詞變成名詞，讓句子的主角變成概念本身：The government's decision to raise taxes …。這樣一句話能裝進更多資訊，語氣也更客觀。閱讀科普或論文時看到一長串名詞片語，先把名詞「還原」成動詞，意思就清楚了。

• The government's decision to raise taxes surprised many people.政府決定加稅，讓很多人意外。（decide → decision）

• The rapid growth of online shopping has changed the retail industry.網購快速成長，改變了零售業。（grow → growth）

• A careful analysis of the data showed a clear pattern.仔細分析資料後，看出一個清楚的規律。（analyze → analysis）

常見的名詞化

名詞化之後常接介系詞：an increase in、the importance of、the effect of … on …。

客觀語氣：被動語態與 It is + p.p. + that

學術寫作的重點是發現本身，不是誰說的，所以常用被動語態與虛主詞句型：It is believed / thought / estimated that + 子句，或改成 S + is believed / thought + to V。第二種寫法的主詞是被談論的事物，不是 people；中文「人們認為」直翻成 People are believed that … 是常見錯誤。

• It is widely believed that sleep plays a key role in memory.一般認為睡眠對記憶有關鍵作用。

• Coffee is thought to reduce the risk of some diseases.咖啡被認為能降低某些疾病的風險。

• It has been shown that regular exercise improves concentration.研究顯示規律運動能提升專注力。

Hedging：不把話說死

一項研究很少能「證明」什麼。學術英文用 may / might / could、tend to、appear to / seem to、be likely to、suggest（而不是 prove）來表示「根據目前證據，可能是這樣」。這不是沒自信，而是精確。學測與分科閱讀的推論題常拿這一點出題：原文說 may，選項寫 definitely 就是錯的。

• Social media may contribute to anxiety among teenagers.社群媒體可能加重青少年的焦慮。

• Students who sleep more tend to get higher grades.睡得多的學生成績往往比較好。

• The results suggest that the new method is effective.結果顯示新方法可能有效。

引用數據的句型

描述變化用 rise / increase / fall / drop + from A to B、by + 幅度；名詞用 an increase / a decrease in + 項目。account for 表示「占……」。the number of + 複數名詞 當主詞是單數（重點是「數目」），a number of + 複數名詞 則是複數（= many）。

• Online sales rose by 15% last year.網路銷售去年成長了 15%。

• The number of international students has increased steadily since 2015.國際學生人數自 2015 年起穩定增加。

• Young people account for nearly half of the app's users.年輕人占這個 app 使用者將近一半。

常見錯誤

• ✗People are believed that exercise improves memory.
  ✓It is believed that exercise improves memory.被動的虛主詞句型是 It is believed that …，或寫成 Exercise is believed to improve memory.。
• ✗Exercise is believed to improving memory.
  ✓Exercise is believed to improve memory.be believed to 後面接原形動詞。
• ✗The number of smartphone users have doubled.
  ✓The number of smartphone users has doubled.the number of 的主詞是 number，單數。
• ✗There was a 20% increase of sales.
  ✓There was a 20% increase in sales.表示某項目的增加用 an increase in。
• ✗This study proves that video games cause violence.
  ✓This study suggests that video games may lead to violence.單一研究不能「證明」因果，學術寫作要用 suggest、may 等 hedging。