Hi, everyone~ 歡迎來到英文庫的文法系列！😍 我是 Gloria～✌🏻
今天要帶大家來認識「肯定句」和「否定句」！相信大家對這兩種句型一定不陌生，因為肯定句和否定句在日常生活中，都是很常用到的表達方式！
那英文的肯定句和否定句到底要怎麼用呢？今天就來一次搞懂吧！Let’s go~😉
肯定句是什麼？
首先，肯定句是什麼呢？我們先來看幾個例句了解：
I am a student.
我是學生He likes fast food.
他喜歡速食They can speak English.
他們會說英語
從這些句子我們可以了解，肯定句就是用來「表示肯定」的句子，能用來表達「真實、肯定」的意思，通常用來敘述一件事實或肯定的事。
否定句是什麼？
看完肯定句之後，接著就來介紹否定句。否定句是什麼呢？我們一樣先看例句來了解：
I am not a student.
我不是學生He does not like fast food.
他不喜歡速食They cannot speak English.
他們不會說英語
看完這些句子你會發現，他們跟剛剛那些句子的差別在於，這些句子都出現了 not 這個否定的詞。所以句子從原本的肯定變成了否定的意思。
所以，我們就能了解，否定句是用來表達「否認、反對、拒絕」等意思的句子，通常在句子裡會出現 not，用來否定某一件事。
如何把肯定句變成否定句？
學完這兩個簡單的觀念，想必你現在一定很清楚肯定句和否定句是什麼。
但是，要怎麼把肯定句變成否定句呢？主要有幾個方法：
1️⃣ 句子有「be 動詞」時，在後面加 not：
be 動詞加 not 的形式還可以用「縮寫」來表達，像是： is not = ‘s not / isn’t、was not = wasn’t 等等：
I am happy. 👉🏻 I am not happy.
He is happy. 👉🏻 He is not happy. = He‘s not happy. = He isn’t happy.
She was happy. 👉🏻 She was not happy. = He wasn’t happy.
They are happy. 👉🏻 They are not happy. = They‘re not happy. = They aren’t happy.
They were happy. 👉🏻 They were not happy. = They weren’t happy.
2️⃣ 句子有「助動詞」時，在後面加上 not：
I will call you. 👉🏻 I will not call you.
He can sing. 👉🏻 He cannot sing.
We have cleaned the table. 👉🏻 We have not cleaned the table.
They should go out. 👉🏻 They should not go out.
通常助動詞後面加 not，也可以用縮寫來表達：
- will not = won’t
- would not = wouldn’t
- cannot = can’t
- could not = couldn’t
- have not = haven’t
- has not = hasn’t
- had not = hadn’t
- should not = shouldn’t
I will not call you. = I won’t call you.
He cannot sing. = He can’t sing.
We have not cleaned the table. = We haven’t cleaned the table.
They should not go out. = They shouldn’t go out.
3️⃣ 句子有「一般動詞」時，在前面加 do not / does not
如果是「一般動詞的過去式」，前面都統一加上 did not
首先，如果句子有一般動詞的話，要注意前面的主詞是什麼，再根據主詞來決定要加 do not 還是 does not。如果主詞是：I / You / We / They 的時候，就要用 do not
I like apples. 👉🏻 I do not like apples.
You like apples. 👉🏻 You do not like apples.
They like apples. 👉🏻 They do not like apples.
那如果主詞是：He / She / It，或是單一個人的時候，就要用 does not。
⚠️ 必須注意的是，在 does not 後面出現的動詞，直接用原形動詞就可以，不用特別加 s：
He likes apples. 👉🏻 He does not like apples.
She likes apples. 👉🏻 She does not like apples.
John likes apples. 👉🏻 John does not like apples.
接下來，如果句子裡有「一般動詞的過去式」的話，在動詞前面統一加上 did not 就可以了！
⚠️ 但是要記得，did not 後面的動詞必須改回原形動詞，不再用過去式動詞。
I found the dog. 👉🏻 I did not find the dog.
He found the dog. 👉🏻 He did not find the dog.
They found the dog. 👉🏻 They did not find the dog.
那 do not / does not / did not 也可以用縮寫的形式來表達：
- do not = don’t
- does not = doesn’t
- did not = didn’t
I do not like apples. = I don’t like apples.
He does not like apples. = He doesn’t like apples.
I did not find the dog. = I didn’t find the dog.
其他否定詞的用法
除了在 be 動詞、助動詞、一般動詞後面加 not 以外，還有一些否定詞可以用來表示否定。嚴格來說，包含這些否定詞的句子都可以稱為否定句：
- no 沒有
- nobody 沒有人
- nothing 沒有事情、沒有東西
- neither 兩者都不
- none 都不 (某範圍以內都沒有)
- never 從不、絕不
相關例句：
I have no friends.
我沒有朋友Nobody is in this room.
這個房間裡沒人I saw nothing in the bag.
包包裡我什麼都沒看到Neither of the boys was here.
這兩個男孩都不在這裡None of the kids went to school.
這些小孩都沒去學校We never drink coffee at night.
我們從來不在晚上喝咖啡
That’s All for Today!
哇～恭喜你看完了！學完是不是很有成就感呢？給你一個大大的讚！👍🏻
希望看完這篇文章能讓你更認識英文的肯定句和否定句。相信只要你常常練習、反覆運用，以後就更能活用這些知識在生活中囉！
以上就是今天的文法系列～那我們就下次見啦！😎
