“把手伸入”可以翻译为 "reach one's hand into" 或 "put one's hand into"。
Reach one's hand into：强调伸手并触及某个空间或物体内部，带有主动探索或获取的意味。
例句：He reached his hand into the box to fetch the toy. （他把手伸进盒子里去拿玩具。）
Put one's hand into：更侧重于描述将手放入某个空间或物体的动作，语气相对中性。
例句：She put her hand into the pocket to check for her keys. （她把手伸进口袋里找钥匙。）