Acupuncture treatment is gentle, painless, and relaxing.

针灸治疗温和，无痛，令人放松。

The operation itself is a brief, painless procedure.

手术本身是一个短暂、无痛的过程。

The journey is relatively painless, even with children.

这趟旅程相对轻松，即使是带着孩子。