little by little

Her English is improving little by little.

她的英语水平正在逐步提高。

Little by little she began to feel better.

她渐渐地感觉好点儿了。

The Panopause is a transient period for women that the functions of ovarium are declining little by little and even totally eliminate.

围是妇女卵巢功能逐渐退、直至完全消失的一时。