“变得友善”可以表达为 "become friendly" 或 "grow more friendly/kind"。以下为具体解析：
1、 "become friendly"
这是最直接、常用的表达，强调从“不友善”到“友善”的状态转变。
例句：
He has become friendlier since he moved to this neighborhood.（他搬到这个社区后变得友善了。）
2、 "grow more friendly/kind"
更强调渐进的过程，适用于描述性格或态度的长期变化。
例句：
Over time, she grew more friendly towards her new colleagues.（随着时间的推移，她对新同事变得友善了。）
其他相关表达："turn friendly"（突然变得友善）
例句：He turned friendly when he realized I was his classmate.（当他发现我是同学时，突然变得友善了。）
"soften (one's attitude)"（态度软化，变得温和）
例句：Her tone softened after hearing his explanation.（听到解释后，她的语气缓和了。）
根据语境选择最合适的表达即可。