1. 表述：know one’s onions
释义：To be very knowledgeable or skilled in some area.（在某领域非常有知识和技能，内行）
例句：I think Nicole is our best candidate for the job—when it comes to corporate accounting, she really knows her onions.
She really knows her onions in the historical field.
If you want advice on stocks, go to ask Livermore. He has an excellent track record and he certainly knows his onions.
2. 表述：soup up
释义：To modify something in order to increase its power or performance.（加大马力）
例句：He's spent a fortune souping up his car for drag racing.
He souped his car up so it will do nearly 120 miles per hour.
If only I could soup up this computer to run just a little faster.
3. 表述：sell like hotcakes
释义：To be sold quickly and in large quantities. （畅销）
例句：This record has been selling like hotcakes—I can't keep it in stock!
The books sell like hot cakes. There 's not much left over.