Which one is correct: "I need to brush up on ..." or "I need to brush up ..."

[Zoli]

A. I need to brush up on my English.
B. I need to brush up my English.

 

[Yankee]

"on"

 

[Skrej]

I would say 'on' as well, but most dictionaries suggest either is correct to my surprise.

Webster
Cambridge
Longman
Collins
Macmillan

 

[probus]

Long ago in India I used to hear "brush it up" and once heard someone say "I will check it up", but neither works in more standard varieties. The "on" is needed.