英語一般現(xiàn)在時的用法
本文章由春喜在線英語于2017.3.14日編輯發(fā)布
（一）定義
一般現(xiàn)在時主要用來表示經(jīng)常性或習慣性的動作，或者是現(xiàn)在的特征或所處的狀態(tài)。如：
He often goes to school on foot every morning.
She is at work now.
They are primary school students.
（二）基本結構
從謂語動詞的分類來看，一般現(xiàn)在時的基本結構主要分三種情況，即：
1、主語+be+其他成分
其中的be，會隨著主語的不同，有am/is/are的變化。am的主語是I，is的主語是第三人稱單數(shù)，are的主語是第一人稱復數(shù)、第二人稱的單數(shù)和復數(shù)、第三人稱的復數(shù)。如：
I am ten years old.
He is in the classroom.
They are in the zoo at the moment.
2、主語+do/does+其他成分
其中，動詞do的主語為第一人稱的單數(shù)和復數(shù)、第二人稱的單數(shù)和復數(shù)、第三人稱的復數(shù)，does的主語為第三人稱的單數(shù)。如：
We always stay up late on Saturday.
You often forget to bring your textbooks with you.
She likes apples very much.
3、主語+情態(tài)動詞+be/do+其他成分
此時，情態(tài)動詞采用的是現(xiàn)在形式，后面的動詞都采用原形。如：
She can be a good teacher in the future.
I must leave for the party now.
（三）動詞的第三人稱單數(shù)
動詞的第三人稱單數(shù)，簡稱三單，是在使用一般現(xiàn)在時中最容易出錯的地方。這與漢語的主謂成分在數(shù)上沒有一致性要求有很大關系。
動詞三單常見的變化規(guī)則有：
1、直接+s
如：works、plays、sweeps
2、“傷心城市”（即以sh、x、ch、s或ss結尾的單詞）加+es
如：washes、fixes、watches、focuses、kisses。
3、以輔音字母+o結尾的+es
如：goes、does、vetoes（否決）
4、以輔音字母+y結尾的，改y為i，再+es
如：studies、flies、dries
5、特殊情況
如：have的三單形式為has。
（四）常見用法
1、表主語現(xiàn)在所處的狀態(tài)
The book is on the desk.
I am very busy.
2、表主語的身份或職業(yè)
She is our English teacher.
His father is a doctor.
3、表主語的特征或特點
The dog often barks at strangers.
He is bad-tempered.
4、表主語的能力
The cat can see well in the darkness.
He is good at swimming.
5、表主語的國籍
Mary comes from Britain.
He is a Chinese.
6、表主語經(jīng)常性或習慣性的行為
Jack sometimes goes hiking by himself on weekends.
They usually visit museums in their spare time.
7、表主語的興趣愛好
She likes reading novels very much.
I want a cup of tea.
8、表天氣或氣候
It is sunny today.
It often rains a lot in spring in Shanghai.
9、表客觀事實或真理
Taiwan lies in the southeast of China.
The sun rises from the east and sets in the west.
10、表按計劃或安排好的或?qū)⒁l(fā)生的動作
這類用法一般只限于start、begin、leave、go、come、arrive、return、take place等。 如：
The train leaves at four tomorrow afternoon.
She comes back home tonight.
11、表將來（在時間和條件狀語從句中）
If he comes, I will tell him about it.
When the plane arrives, she will meet him herself.
12、用在格言、警句中
Pride goes before a fall. （驕必敗。）
Time is money. （時間就是金錢。）
13、表過去
1） 用于某些動詞（tell、say、hear、learn等）表示不確定的過去時間。如：
She tells me Jack will come tomorrow. （她告訴我杰克明天要來。）
I hear that he won the first prize in the competiton last week. （我聽說他在上周的比賽中得了第一名。 ）
2）當要陳述一個客觀事實時，有時即使有過去時間狀語也可用一般現(xiàn)在時。如：
The story is set in the summer of 1937. （故事的背景是1937年夏天。）
The story begins in the year 1937. （故事開始于1937年。）
（五）常見的標志性詞語
1、頻度副詞
按照頻度高低，常見的頻度副詞如下：
always
usually
often
sometimes
seldom
never
2、every+時間單位
every day/week/month/year
3、一天里的時間
in the morning/afternoon/evening
at noon/night
（六）句型轉(zhuǎn)換
1、謂語動詞為be動詞或情態(tài)動詞的句子
此時，如果是要轉(zhuǎn)換為否定句，則直接在be動詞或情態(tài)動詞后加not。如：
He can drive a car.
He cannot (或can't) drive a car.
She is on the playground.
She is not (或isn't) on the playground.
如果要轉(zhuǎn)換為一般疑問句或?qū)澗€部分提問，則直接把be動詞或情態(tài)動詞提到句首即可。如：
He can drive a car.
Can he drive a car? Yes, he can. / No, he can't.
What can he drive? (提問a car）
She is on the playground.
Is she on the playground. Yes, she is. / No, she isn't.
Where is she? (提問on the playground)
2、謂語動詞為其他動詞的句子
此時，如果是要轉(zhuǎn)換為否定句，需要借助助動詞do/does，在后面加not，同時原有的動詞要恢復原形。如：
He often goes to work by car every day.
He doesn't often go to work by car every day.
如果要轉(zhuǎn)換為一般疑問句或?qū)澗€部分提問，需要借助助動詞do/does，提到句首，原有動詞要恢復原形。如：
She seldom goes hiking on her own.
Does she seldom go hiking on her own? Yes, he does. / No, he doesn't.
What does she seldom do on her own? (提問goes hiking）
【注意】
1、如果原句的主語為第一人稱，變?yōu)橐话阋蓡柧浠驅(qū)澗€部分提問時，要改為第二人稱。如：
I often have English classes on Friday.
Do you often have English classes on Friday? Yes, I do. / No, I don't.
What classes do you often have on Friday? (提問English）
2、如果原句中含有some，變?yōu)榉穸ň浠蛞蓡柧鋾r，一般要改為any。如：
There are some oranges on the plate.
There aren't any oranges on the plate.
Are there any oranges on the plate? Yes, there are. / No, there aren't.
Where are there any oranges? (提問on the plate)