動名詞是動詞的一種非謂語形式。動名詞的構(gòu)成和現(xiàn)在分詞相同。

動名詞具有名詞的特點：可在句中作主語、賓語和標(biāo)語。動名詞也具有動詞的某些特點：要求賓語和帶有狀語，這是就構(gòu)成了動名詞短語。動名詞也有主動和被動、一般和完成等形式。以DESIGN為例：主動態(tài)

被動態(tài)

般式 Designing Being designed

完成式 Having designed Having being designed

動名詞和動名詞短語的用法

動名詞及短語在句中可作主語、賓語和表語。例如：（1） Heating the water changes it into vapor. 把水加熱可以使水變?yōu)檎羝＃℉eating the water在句中作主語，water是heating的賓語。）

（2）Closing the switch connects the cranking motor to the battery. 合上開關(guān)就把啟動馬達(dá)與蓄電池接通了。（句中closing the switch作主語，switch為closing的賓語。）

（3）Oxygen does not burn, but does support burning. 氧布自燃，但能助燃。（burning是動名詞，作support的賓語。）

（4）Energy is involved in doing work, or in heating on object. 能量在于它能做功，或使物體變熱。（動名詞doing和heating均為介詞in的賓語。）

（5）In the dynamo, mechanical energy is used for rolating the armature between the poles of an electromagnet. 在直流發(fā)電機中，機械能被用來轉(zhuǎn)動電磁鐵兩極之間的電樞。（動名詞rotating是介詞for的賓語。）

（6）One way to fit the pieces of a broken iron bar together is heating the iron until it softens and pounding it with a hammer. 把一根斷成數(shù)截的鐵棍連接起來的一個方法就是把鐵加熱至軟化，然后用鐵錘去鍛打。（句中heating和pounding均為表語。）

動名詞的被動態(tài)

當(dāng)動名詞的邏輯主體是動名詞的動作對象時，該動名詞通常用被動形式。例如：

（1）When a vapor condenses, the energy that it absorbed in being baporized is again released as heat. 當(dāng)蒸汽冷凝時，它汽化時所吸收的能量又以熱的形式釋放出來。（it用來代替vapor，it時vaporize這一動作的承受者，所以要用動名詞的被動形式being vaporized.）

（2）It is assumed that every substance which is capable of being magnetized consists of a very large number of molecular magnets….人們假定，能夠被磁化的各種物質(zhì)都是由大量的分子磁體組成的….（句中which用來代替substance，which時動詞magnetize這一動作的對象，所以magnetize的動名詞應(yīng)用被動形式。）