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動詞與時態中級

情態動詞

Modal verbs

Can、could、may、might、must、should、will、would 等放在原形動詞之前，用來表達能力、許可、義務、建議，以及對現在與過去的推測。

編寫：OpenTOEIC更新日期:

練習 60 題

共同特點

S + modal + V (原形)S + modal + be + V3 (被動)S + modal + have + V3 (過去 / 推測)
  • 後面接不帶 to 的原形動詞：She can speak three languages.
  • 第三人稱不加 -s：He must sign（不是 musts）。
  • 否定加 not，疑問句將情態動詞移到主詞前：cannot/can't, should not, may not, Could you ...?
  • 兩個情態動詞不能連用：不說 will can，要說 will be able to。
  • 被動：modal + be + V3；完成：modal + have + V3；進行：modal + be + V-ing。

選出情態動詞後面的動詞形式

Part 5 關於情態動詞的題目通常不考意思，而是考後面接的形式。需要區分的形式有五種，而且全都以原形動詞（V、be 或 have）開頭。

  • 情態動詞之後絕不接 V-ing、V3、to V 或加 -s 的動詞：should submits、can submitted、must to submit 全都是錯的。
  • 如果句中有過去時間點（yesterday, last week）與情態動詞連用，答案通常是 have + V3 的形式。
形式何時選擇例句
modal + V主詞自己做，空格後有受詞Staff must wear safety goggles.
modal + be + V3主詞受到影響，沒有受詞Goggles must be worn at all times.
modal + be + V-ing現在或未來正在進行的事Ms. Ford may be attending another meeting.
modal + have + V3對過去的推測、遺憾The courier must have left the box at reception.
modal + have been + V3同上，但為被動The error should have been reported earlier.
例句
  • Expense reports should be submitted within ten days of the trip.費用報告應在出差後十天內提交。
  • The delivery might have been delayed by the snowstorm.這批貨可能因為暴風雪而延誤了。

能力與許可：can、could、be able to、may

  • can：現在的能力、非正式的請求或給予許可。could：過去的一般能力，或禮貌的請求。
  • be able to：用於 can 沒有的時態（will be able to、has been able to），以及過去某一次成功做到的具體事情：We were able to finish on time（這種肯定句通常不用 could）。
  • may：正式的請求許可（May I ...?），以及公告中的允許（Employees may park in Lot B）。may not = 不得、不允許。
例句
  • Visitors may use the conference room after 5 P.M.訪客可在下午 5 點後使用會議室。
  • Thanks to the new software, we were able to cut processing time in half.多虧了新軟體，我們得以將處理時間縮短一半。
  • Could you send me the revised quote by Thursday?您能在星期四前把修訂後的報價單寄給我嗎？

義務、必要性與建議

  • should 也可表示預期會發生的事：The package should arrive by Friday（= 應該會到）。
  • 此外還有 be required to、be supposed to、be obliged to（被動形式，表示義務），常見於公司公告。
結構意思說明
must + V必須（說話者認為有必要、書面規定）過去式用 had to
have to / has to + V必須（由於規定、外在情況）可用於所有時態
must not (mustn't) + V禁止、不得與 don't have to 完全不同
don't have to / don't need to / needn't + V不需要、非強制Needn't + 原形動詞
need to + V需要Need 在此是一般動詞
should / ought to + V應該否定：shouldn't, ought not to
had better + V最好（否則會有後果）否定：had better not + V
例句
  • All visitors must sign in at the front desk.所有訪客都必須在櫃檯簽到。
  • You don't have to bring a laptop; one will be provided.你不需要帶筆記型電腦；我們會提供一台。
  • Employees must not share their passwords with anyone.員工不得與任何人分享自己的密碼。
  • We had better confirm the booking before prices go up.我們最好在漲價前確認訂位。

用其他時態表達情態動詞的意思

情態動詞沒有 V-ing、V3 或未來形式，所以不能說 will must 或 has could。需要其他時態時，就用意思相同的替代片語。

  • 談過去的義務一律用 had to：Yesterday we had to work late，不寫成 must worked。
  • 過去式的 could 只表示一般能力；某一次成功做到具體的事，要用 was/were able to 或 managed to。
  • 這些片語可以放在另一個情態動詞後面：may have to、might be able to、should be allowed to。
情態動詞過去未來現在完成式
must（必須）had towill have tohas/have had to
can（能夠）could / was able towill be able tohas/have been able to
may, can（獲准）was allowed towill be allowed tohas/have been allowed to
need to（需要）needed towill need tohas/have needed to
例句
  • Next year, customers will be able to track their orders on our app.明年起，顧客將能在我們的應用程式上追蹤訂單。
  • We have had to postpone the launch twice because of supply problems.由於供貨問題，我們已經不得不兩度延後發表會。

對現在與過去的推測

  • should have + V3：本來應該做（但沒做）── 責備、遺憾。shouldn't have + V3：本來不應該做。
  • could have + V3：本來可以（但沒有發生）。
  • needn't have + V3：做了但結果其實不必要；didn't need to + V：當時不需要（通常也沒做）。
  • 注意：否定的推測用 can't，不用 mustn't。
確定程度現在：modal + V過去：modal + have + V3
幾乎可以確定must bemust have left
有可能may / might / could bemay / might / could have left
肯定不是can't / couldn't becan't / couldn't have left
例句
  • The lights are off, so the staff must have gone home.燈都關了，員工一定已經回家了。
  • Mr. Silva can't have received the email; his inbox was down all morning.Silva 先生不可能收到那封電子郵件；他的收件匣整個早上都故障。
  • We should have ordered more brochures for the exhibition.我們當初應該為展覽多訂一些宣傳手冊。

Will、would 與禮貌用語

  • Will/Would you + V?：請人幫忙（would 更客氣）。
  • Would you like + to V / N?：邀請。I would like to + V：想要（客氣的說法）。
  • Would you mind + V-ing?：可否麻煩你……。Would you mind if I + V2?：我……你會介意嗎。
  • would rather + V (than + V)：寧願。would 也是間接引述中 will 的過去式。
  • Should + S + V, ...：第一類條件句的正式倒裝。
例句
  • Would you mind rescheduling our meeting to Thursday?您介意把我們的會議改到星期四嗎？
  • Should you require further assistance, please contact our support team.如需進一步協助，請聯絡我們的支援團隊。

含情態動詞的句子中副詞的位置

表示頻率、程度或方式的副詞通常放在情態動詞與主要動詞之間。Part 5 常把空格設在這個位置，答案是副詞而不是形容詞。

S + modal + 副詞 + VS + modal + 副詞 + be + V3S + modal + be + 副詞 + V3
  • 主動：The new software can easily handle large files.
  • 被動：副詞放在情態動詞之後，或放在 be 與 V3 之間：can easily be accessed 和 can be easily accessed 都正確。
  • 否定：not 緊接在情態動詞之後，程度副詞放在 not 之後：You should not necessarily accept the first offer.
  • 常見片語：will soon be, can now be, should always be, must first be, may also be, will likely be。may well + V 表示很有可能：Prices may well rise next year.
例句
  • All visitors must first register at the security desk.所有訪客都必須先到警衛櫃台登記。
  • Tickets can now be purchased through our mobile app.現在可以透過我們的行動應用程式購票。

多益解題技巧

  1. 快速得分的規則：情態動詞（can, could, may, might, must, should, will, would）之後一律接不帶 to 的原形動詞。空格緊接在 should、must、will 之後時，選原形動詞（submit），刪去 submits/submitted/submitting/to submit。被動：modal + be + V3。
  2. 區分 ought to / have to / need to / be able to + V（有 to）與 must / should / can + V（沒有 to）。題目也常考 had better + V 和 would rather + V。
  3. 以 Should 開頭的倒裝條件句在 Part 6 的電子郵件中非常常見：Should you have any questions, please contact ...（= If you have any questions）。句首空格 + you have → 選 Should。
  4. 禮貌的邀請、請求：Would you mind + V-ing、Would you like + to V、Could you please + V。回答 mind 的問句時，Not at all 表示同意。

常見錯誤

錯誤: All applicants must to submit a cover letter.

正確: All applicants must submit a cover letter.

must 之後接不帶 to 的原形動詞。

錯誤: The manager cans approve the request.

正確: The manager can approve the request.

情態動詞不加 -s。

錯誤: You mustn't bring lunch; it is provided.

正確: You don't have to bring lunch; it is provided.

Mustn't = 禁止；表示不需要時用 don't have to/needn't。

錯誤: Would you mind to close the door?

正確: Would you mind closing the door?

Mind + V-ing。

錯誤: She must have forget the password.

正確: She must have forgotten the password.

Modal + have + V3。

練習題（附解答）

  1. 1.Visitors must ------- their identification at the front desk.

    1. (A) to show
    2. (B) showing
    3. (C) show
    4. (D) showed
    查看解答與解析

    答案: (C) show

    情態動詞 must 之後接原形動詞（不加 to）→ show。to show、showing、showed 都不對。

  2. 2.All overtime hours must ------- by a department supervisor at least one day in advance.

    1. (A) approve
    2. (B) be approved
    3. (C) approving
    4. (D) been approved
    查看解答與解析

    答案: (B) be approved

    加班時數是被批准的（by a department supervisor）→ 情態助動詞後用被動語態：be approved。approve 是主動，缺少受詞；approving 和 been approved 不能直接放在 must 後面。

  3. 3.Thanks to the extra staff, the warehouse ------- able to ship every holiday order on time last year.

    1. (A) could
    2. (B) had
    3. (C) did
    4. (D) was
    查看解答與解析

    答案: (D) was

    be able to 的過去式，搭配 last year → was able to。could、had、did 都不能搭配 able to。

  4. 4.New employees ought ------- the safety manual before operating any of the machinery.

    1. (A) read
    2. (B) reading
    3. (C) reads
    4. (D) to read
    查看解答與解析

    答案: (D) to read

    ought 一定搭配 to + V → to read。read、reading、reads 不是少了 to 就是形式錯誤。

  5. 5.You ------- bring your own laptop to the workshop because computers will be provided.

    1. (A) must
    2. (B) don't have to
    3. (C) have to
    4. (D) should
    查看解答與解析

    答案: (B) don't have to

    電腦會提供 → 不必自備：don't have to（沒有必要）。must、have to、should 都表示應該／必須帶，與句中的理由相反。

  6. 6.The report ------- have been sent to the wrong address, as the client never received it.

    1. (A) need
    2. (B) must
    3. (C) can
    4. (D) would
    查看解答與解析

    答案: (B) must

    根據證據（客戶沒收到）對過去做出肯定推論 → must have + V3。need have 只用於否定（needn't have），can have 不用於肯定句，would have 需要條件。

  7. 7.Mr. Novak ------- have seen the revised schedule, because it was posted only after he left for the airport.

    1. (A) can't
    2. (B) needn't
    3. (C) should
    4. (D) must
    查看解答與解析

    答案: (A) can't

    行程表是在他離開之後才公布的 → 他一定不可能看過：can't have seen。must have seen（想必看過）和 should have seen（當初應該看）與理由矛盾；needn't have seen（看了但其實不必）也矛盾。

  8. 8.Mr. Harris ------- have reserved the conference room earlier; now all the rooms are booked.

    1. (A) should
    2. (B) must
    3. (C) will
    4. (D) can
    查看解答與解析

    答案: (A) should

    should have + V3 表示本來應該做卻沒做（現在房間都被訂光了）。must have 是推測，will have 是未來完成式，can have 結構錯誤。

  9. 9.Would you mind ------- the sales figures before they are sent to the regional manager?

    1. (A) checking
    2. (B) to check
    3. (C) check
    4. (D) checked
    查看解答與解析

    答案: (A) checking

    Would you mind + V-ing → checking。to check、check、checked 都不能接在 mind 後面。

  10. 10.------- the shipment arrive damaged, please photograph the packaging before opening it.

    1. (A) If
    2. (B) Would
    3. (C) Should
    4. (D) Had
    查看解答與解析

    答案: (C) Should

    主詞後面是 arrive（原形動詞），且主要子句是祈使句 → 條件句倒裝 Should the shipment arrive（= If the shipment arrives）。If 需要用 arrives；Would 和 Had 在這裡無法與原形動詞構成條件句倒裝。

練習題

60 題 Part 5 題型，一次一題，每題作答後立即附上解析。

開始練習

常見問題

什麼是情態動詞？

情態動詞（modal verbs）是 can, could, may, might, must, shall, should, will, would 這些放在主要動詞前面的助動詞，用來加上能力、許可、義務、建議或推測的意思。它們有三個特點：後面接不帶 to 的原形動詞、第三人稱不加 -s，以及在否定句和疑問句中自己充當助動詞（cannot、Could you ...?）。

Must 和 have to 有什麼不同？

兩者都表示必須。Must 通常表示說話者認為有必要，或是公告中寫明的規定（All visitors must sign in）。Have to 強調來自外在情況或規定的義務，而且可用於所有時態（had to, will have to）。由於 must 沒有過去式，談過去的義務一律用 had to。

Mustn't 和 don't have to 有什麼不同？

這兩個結構的意思幾乎相反。must not (mustn't) + V 表示禁止、不可以做：Employees must not share their passwords。don't have to / don't need to / needn't + V 表示不需要、不強制，做了也可以：You don't have to bring a laptop。在 Part 7 閱讀公告時，搞混這兩個結構是非常常見的錯誤。

"Should have + V3" 是什麼意思？

should have + V3 表示當初應該做卻沒有做，用來表達遺憾或責備：We should have ordered more brochures。shouldn't have + V3 表示當初不該做（卻做了）。同一句型的其他形式：must have + V3（想必已經）、could have + V3（本來可以）、can't have + V3（不可能已經）。

Can 和 be able to 有什麼不同？

在現在式中，can 和 am/is/are able to 意思相近，但 can 較常用。在 can 沒有的時態（will be able to、has been able to）以及另一個情態動詞之後（might be able to），就必須用 be able to。談過去某一次成功做到具體的事時，要用 was/were able to 而不是 could：We were able to finish on time。

"Should you have any questions" 是什麼意思？

這是第一類條件句的倒裝：省略 if，把 should 移到句首。Should you have any questions, please contact us = If you have any questions, please contact us。這個結構在 Part 6 和 Part 7 正式電子郵件的結尾非常常見。Should + 主詞 之後接原形動詞（have, require, need），不是 has 或 having。