"Gradually understand" in Engpsh can be expressed as "gradually come to understand" or simply "gradually understand".
The phrase comes from the verb "to understand", which means to have knowledge or perception of a situation or idea, combined with the adverb "gradually", which means happening or developing slowly or by degrees.
Examples:
I gradually came to understand the importance of saving money.
(我逐渐明白了存钱的重要性。)
He gradually understood the concept after repeated explanations.
(他在反复解释后逐渐明白了这个概念。)