她一点一点地攒钱，终于买到了心仪的笔记本电脑。

She saved money ___bit-by-bit until she could afford the laptop she wanted.

他一点一点地修复这辆古董车，确保每个零件都完美无缺。

He restored the vintage car ___bit-by-bit, making sure every part was flawless.