I've tipped you a wink or signalled to you on the sly many times, but before you took the hint others had already noticed.

我多次向你使眼色，又给你递暗号，别人都明白了，你却没有反应。

《新英汉大辞典》

Fried mozzarella will be the appetizer to a roast pork sandwich that is a sly take on char siu bao, a food close to Mr. Torrisi’s heart.

炸干酪只是开胃菜，而主菜是一道烤猪肉三明治，三明治暗中巧妙借鉴了托里西的心水食物——叉烧包。

youdao

An old Fox, crafty and sly, had a den in the rocks, on a hill near her house.

在她家不远处的小山上住着一只狡猾的老狐狸。

youdao

Since I have learned the hard way that a diet Coke gulped on the sly the final day of your stay will almost surely show up on your bill, I have always wondered about the robe scenario.

CNN: Is it OK to steal hotel amenities?

So they tried to keep up appearances while indulging in a sensual life on the sly.

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Playing music from his big-band tribute to Nat King Cole's Spanish-language albums, saxophonist David Murray's Cuban Ensemble occupied the same space as Mr. Bernstein and his Millennial Territory Orchestra, which drew from its new album, a take on the music of Sly Stone.

WSJ: Winter Jazzfest | The Broad Tent of Jazzfest | By Jim Fusilli