網友3e54675
2012-09-15
am/ is/ are/was/ were 是系動詞的具體形式
be用在情態動詞、不定式之後。be 之後接表語（名詞、形容詞、副詞、分詞、不定式、動名詞。表語從句）
如： you should be here
he wants to be a doctor。
linjiabin5
2012-09-15
1。 AUXYou use be with a present participle to form the continuous tenses of verbs。 後接動詞的現在分詞，構成動詞進行體
例：This is happening in every school throughout the country。
這在全國各校都正在發生。
例：She didn‘t always think carefully about what she was doing。
她不總是仔細思考自己正在做什麼。
2。 be going to
See： going
3。 AUXYou use be with a past participle to form the passive voice。 後接動詞的過去分詞，構成被動語態
例：Her husband was killed in a car crash。
她丈夫在一場車禍中被奪去了性命。
例：Similar action is being taken by the U。S。 government。
類似的行動正被美國政府所採取。
4。 AUXYou use be with an infinitive to indicate that something is planned to happen， that it will definitely happen， or that it must happen。 後接動詞不定式，表“安排、註定、必然”等意
例：The talks are to begin tomorrow。
會談將於明天開始。
例：It was to be Johnson’s first meeting with the board in nearly a month。
那將是近一個月來約翰遜與董事會的首次會面。
5。 be about to
See： about
6。 AUXYou use be with an infinitive to say or ask what should happen or be done in a particular situation， how it should happen， or who should do it。 後接動詞不定式，用於說明或詢問特定情況下應該會怎樣、怎樣做、誰來做等
例：What am I to do without him？
沒有他我該怎麼辦？
例：Who is to say which of them had more power？
誰知道他們當中誰有更大權利？
7。 AUXYou use was and were with an infinitive to talk about something that happened later than the time you are discussing， and was not planned or certain at that time。 was和were接不定式表示說話時間之後發生的事
例：He started something that was to change the face of China。
他發起了某項後來改變了中國面貌的行動。
8。 AUXYou can say that something is to be seen， heard， or found in a particular place to mean that people can see it， hear it， or find it in that place。 後接seen、heard、found，表“可見到、可聽到、可發現”之意
例：Little traffic was to be seen on the streets。
路上幾乎沒有車輛可見。
網友9b613ef
2012-09-28
be doing sth。是am is are。過去式是was were。在不同的地方有不同用法
