英语短语turn from的核心含义是“从...（状态/方向/行为）转变”，具体义项和用法可分为以下几类，结合例句说明更清晰：
指将身体部位（如头、脸）、目光或注意力从某个方向/事物上移开。
She turned her eyes from the scary movie to hold her friend’s hand.（她把目光从恐怖电影上移开，握住朋友的手。）
The speaker turned from the audience to check his notes.（演讲者从观众身上转开视线，查看笔记。）
表示状态/颜色/性质的转变，常与“to”搭配（turn from A to B）。
In autumn, the maple leaves turn from green to bright red.（秋天，枫叶从绿色变成鲜红色。）
His mood turned from excitement to disappointment when he heard the news.（听到消息后，他的心情从兴奋变成失望。）
指不再继续某种行为、习惯或活动，后接动名词（doing）或名词。
He decided to turn from smoking after his doctor warned him.（医生警告后，他决定戒烟。）
She turned from gossiping once she realized it hurt others.（意识到说闲话伤人后，她不再说了。）
指不再忠诚于或放弃支持某人、信仰或承诺。
Don’t turn from your friends when they’re in trouble.（朋友有困难时，别背弃他们。）
The politician turned from his campaign promises after being elected.（这位政治家当选后背弃了竞选诺言。）
1、 搭配结构：
turn from A to B：从A转向/变成B（最常见，覆盖“转开”“变成”“转变行为”等义）；
turn from doing sth：停止做某事（后接动名词）；
turn from sb/sth：背弃某人/某事（直接接对象）。
2、 易错区分：
turn from vs turn away from：
“turn away from”更强调主动避开/拒绝（如：He turned away from the beggar. 他避开了乞丐）；
“turn from”侧重从原状态的“转变”（如：He turned from begging to working. 他从乞讨转向工作）。
转开：The mother turned from the stove to answer the phone.（妈妈从炉子旁转过来接电话。）
变成：The sky turned from blue to gray as the storm approached.（暴风雨来临时，天空从蓝色变成灰色。）
放弃：She turned from her high-paying job to pursue art.（她放弃高薪工作去追求艺术。）
背弃：He turned from his former beliefs after the accident.（事故后，他背弃了以前的信仰。）
总结：“turn from”的核心是“从原状态的转变”，具体含义需结合上下文判断，但都围绕“离开/改变原来的方向、状态或行为”展开。