"firm up" in Chinese (Simplified)
巩固强化紧实（身体）
Definition
使某事变得更强、更明确或更有保障。也可以指让身体或肌肉变得更紧实、结实。
Usage Notes (Chinese (Simplified))
属于非正式日常表达，常见于商务（如“firm up a plan”）、运动健身（如“firm up your muscles”）和确定细节（如“firm up the date”）时。通常和‘计划’、‘细节’、‘安排’等名词一起用。
Examples
We need to firm up the meeting time.
我们需要**确定**会议时间。
She does yoga to firm up her muscles.
她做瑜伽来**紧实**肌肉。
Let’s firm up our travel plans this week.
我们这周要**敲定**旅行计划。
Can you firm up the details and get back to me?
你能**落实**细节再回复我吗？
I need to firm up before summer hits.
夏天来之前我得**锻炼紧实**些。
Once we firm up the schedule, I’ll book the tickets.
一旦我们**确定**日程，我就订票。