I think you should read more English books and do more English exercise books.
Yet, the fastest way to improve your English is use English to communicate with others.
An English Identity Of Usage 26
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
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Bi English Identity Of Usage 23
Z Y X W T S R Q P O N M L K J H G F E D C B A
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Putonghua English Identity Of Usage 2013
Zi You Xuan Wen Ti Suo Ren Qu Pian Ou Na Mei Li Ke Ju He Guo Fa Er Ding
Chu Ben An 23
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參考: Putonghua On An English Usage 23+26 Language's Use