With no one ___(turn to) for help,the boy had to start to look for food by himself.
问题描述：
With no one ___(turn to) for help,the boy had to start to look for food by himself.
答
填turned to（过去式）,因为后句用了had是过去式表示整件事发生在过去,所以用一般过去时
因为没有人可以求助,所以这个小男孩不得不开始自己寻找食物.