cinch

这个数学题对他来说太简单了，简直是小菜一碟。

This math problem was a ___cinch for him.

对熟练的厨师来说，做这道菜简直是易如反掌。

For an experienced cook, making this dish is a ___cinch.

有了他的帮助，这次项目成功是十拿九稳的事。

With his help, the success of this project is a ___cinch.