倒裝句 (inversion) 就是正常詞序顛倒的句子，其中以主詞和動詞順序對調的情況最為普遍。所以，英文中最常見的倒裝句就是問句。總的來說，陳述句為正常詞序，即「主詞 + 動詞 (片語)」，而問句為倒裝句，詞序變成「BE 動詞 + 主詞」、「Can、Will 或 Would 等語氣助動詞 + 主詞」或「Do、Does、Did 或其他助動詞 + 主詞」。例如：
- John is writing an email. (約翰正在寫電子郵件)
Is John writing an email? (約翰正在寫電子郵件嗎？) - Mary would like to go to the concert. (瑪麗想去聽那場演唱會)
Would Mary like to go to the concert? (瑪麗想去聽那場演唱會嗎？) - They like to play the piano. (他們喜歡彈鋼琴)
Do they like to play the piano? (他們喜歡彈鋼琴嗎？) - He has been invited. (他已接到邀請)
Has he been invited? (他接到邀請了嗎？)
英文中最常見的倒裝句型是問句 (如上述)，其次就是下列三種倒裝句型。此外，還有若干比較少見的倒裝句型，在此就略過不談。但不管是那一種倒裝句，主要子句的主詞和動詞詞序都要對調，而其目的都是在加強特定字詞的語氣或起強調作用。
否定副詞
在正式文體中，當 never、hardly、seldom、rarely 和 scarcely 等否定副詞被置於句首來加強語氣時，主句須變成倒裝句，主詞和助動詞或語氣助動詞的順序要對調。例如：
- Never have we heard anything so ridiculous. (我們從未聽過如此荒謬的事情)
原句：We’ve never heard anything so ridiculous. - Hardly had I finished the article when the light went out. (我剛寫完文章，燈就熄了)
原句：I had hardly finished the article when the light went out. - Seldom do the customers receive any apology when mistakes are made. (出錯的時候，顧客很少接到道歉)
原句：The customers seldom receive any apology when mistakes are made. - Rarely are the designs reproduced exactly as illustrated. (這些重製的圖案鮮少跟設計圖完全一樣)
原句：The designs are rarely reproduced exactly as illustrated.
以 Not 做開頭的詞句
當 not + 介系詞片語或 not + 附屬子句被挪到句首時，主句須變成倒裝句，主詞和助動詞或語氣助動詞的詞序要對調。例如：
- Not for a moment did Allen think he would get the job, so he was amazed when he was offered the job. (艾倫從不認為他會得到那份工作，所以當他得到時，他驚呆了)
原句：Allen didn’t think he would get the job for a moment, so he was amazed when he was offered the job. - Not for a moment do I believe that story. (我絕不相信那個說法)
原句：I don’t believe that story for a moment. - Not till I have got all the information can I comment further. (我要得到全部訊息之後才能進一步評論)
原句：I cannot comment further till I have got all the information. - Not until I got home did I realize my cellphone was missing. (我回到家之後才知道我的手機不見了)
原句：I didn’t realize my cellphone was missing until I got home.
Here 和 there
當 here 和 there 用作地方或場所副詞，意為「這裡」和「那裡」時，其後的主詞和動詞要倒裝，但這種倒裝無須藉助於語氣助動詞或其他助動詞，只要將主詞和主動詞的詞序對調即可。這種用法最常見的句型是 Here is + 主詞、Here comes + 主詞、There is + 主詞、there goes + 主詞。Here 和 there 用於句首旨在加強語氣及引起注意。例如：
- Here’s the grammar book I said I’d lend you. (這就是我說要借你的文法書)
- Here comes your taxi. (你叫的計程車來了)
- Here comes James on his new bike. (詹姆斯騎著他的新腳踏車來了)
- There’s the restaurant where that kind of delicacy is served only once every week. (那就是那家每週僅供應一次那種美味佳餚的餐廳) － 這裡的 There’s 或 There is 並不是「有」的意思。
- There goes my brother on his motorbike. (我弟弟騎著他的機車離開了)
- There goes the bus. (公車走了)
- I opened the window and looked out and there stood my girlfriend. (我打開窗戶往外看，而我女朋友就站在那裡)
- I opened the window and looked out and there was my girlfriend. (我打開窗戶往外看，而我女朋友就在那裡)