释义：
turn back 转身，回来，使回来
turn back 字面含义为转身回来，可以表示“回头看”，“回来”或使别人“回来”等。
例句：
Even though she never turned back, she knew Tom was behind her.
虽然她没有转身，但却知道汤姆就在她身后。
They both turned back to look at the building.
他们同时转身看了看那栋楼。
You have a right to turn back if you're scared.
如果你害怕的话，可以回去。
对话：
A: A lot of snow is falling. Should we turn back?
正下着鹅毛大雪呢，我们要不要回去？
B: No, let's keep going till we get there.
不，我们得一直走到底。
