The French feel passionately about their native tongue.

法国人非常热爱他们的母语。

Her lapse into German didn't seem peculiar. After all, it was her native tongue.

她开始说德语并不奇怪，毕竟那是她的母语。

I tried speaking to her in her native tongue.

我试着用她的本族语和她说话。

Spanish is my native tongue.

西班牙语是我的母语。

Is your native tongue Chinese or English?

你的母语是汉语还是英语？