動名詞是非限定動詞的一種形式，由動詞原形+ing構(gòu)成。它既有動詞的特征，又有名詞的特征，故稱。動名詞也有時(shí)態(tài)和語態(tài)的變化，如表所示（以及物動詞write為例），不及物動詞沒有語態(tài)的變化。

　　時(shí)態(tài)/語態(tài) 主動 被動

　　一般式 writing being written

　　完成式 having written having been written

　　6.1 動名詞作主語、賓語和表語

　　1）作主語。例如：

　　Fighting broke out between the South and the North. 南方與北方開戰(zhàn)了。

　　2）作賓語

　　a. 有些動詞可以用動名詞作賓語。例如：

　　admit 承認(rèn) appreciate 感激 avoid 避免 complete完成 consider認(rèn)為 delay 耽誤

　　deny 否認(rèn) detest 討厭 endure 忍受 enjoy 喜歡 escape 逃脫 fancy 想象

　　finish 完成 imagine 想象 mind 介意 miss 想念 postpone推遲 practice 訓(xùn)練

　　recall 回憶 resent 討厭 resume 繼續(xù) resist 抵抗 risk 冒險(xiǎn) suggest 建議

　　face 面對 include 包括 stand 忍受 understand 理解 forgive 寬恕 keep 繼續(xù)

　　例如：Would you mind turning down your radio a little, please? 你把收音機(jī)音量調(diào)小一點(diǎn)，好嗎

　　The squirrel was lucky that it just missed being caught. 這松鼠幸運(yùn)得很，剛逃避了被逮住的厄運(yùn)。

　　b. 有些結(jié)構(gòu)后面可以用動名詞作賓語或其他成分。例如：

　　admit to prefer…to be used to lead to devote oneself to object to

　　stick to no good no use be fond of look forward to be proud of

　　be busy can't help be tired of be capable of be afraid of think of

　　burst out keep on insist on count on set about

　　put off be good at take up give up be successful in

　　3）作表語，對主語說明、解釋。例如：

　　Her job is washing, cleaning and taking care of the children. 她的工作是洗刷、清掃和照顧孩子。

　　比較：She is washing, cleaning and taking care of the children.

　　4）作定語，一般表示所修飾名詞事物的用途。例如：

　　a writing desk=a desk for writing 寫字臺

　　a swimming pool=a pool swimming 游泳池

　　有些動名詞作定語，與所修飾的名詞關(guān)系比較復(fù)雜。例如：

　　boiling point=a temperature point at which something begins to boil 沸點(diǎn)

　　a walking tractor=a tractor which a driver can operate while he or she is walking behind it 手扶拖拉機(jī)

　　6.2 worth 的用法

　　worth, worthy, worthwhile都是形容詞，意為"值得"。

　　1. worth： be worth + n.　 當(dāng)名詞為金錢時(shí)，表示"…… 值得……"

　　常見的有It ’s worth while to do./ It ’s worth（someone’s）while doing

　　be worth doing sth.　"……某事值得被做"

　　The question is not worth discussing again and again. 這問題不值得反復(fù)討論。

　　2. worthy：be worthy of +n.　當(dāng)名詞為抽象名詞時(shí)表示"……值得……"

　　be worthy to be done "某事值得被做"

　　The question is not worthy to be discussed again and again.

　　3. worthwhile：be worthwhile to do sth　 "值得做某事"

　　It is worthwhile to ask him to join the club.值得邀請他加入俱樂部。

　　典型例題

　　It is not ____ to discuss the question again and again.

　　A. worth　 B. worthy　C. worthwhile　D. worth while

　　答案C. 由worth的用法可知，此句只適合詞組be worthwhile to do sth.。選C。