lose touch（常与with连用(本义是）失去联系；停止联系

No one whom David has taught seems ever lose touch with him.他控制不住自己的感情。

No one whom he has taught seems ever to lose touch with him.他所教过的学生似乎没有一个和他疏远。

No one whom Mr Smith has taught seems ever to lose touch with him.史密斯先生教过的人至今似乎没谁与他失去联系。

翻译We speak German at home so that the boys don't lose touch with their language.并指出这里的touch和lose touch是什么意思？？
可译成"在家中用德语交流的目的是培养孩子们说母语的语感."
lose touch在此句中要灵活翻译.