狗也知道吗 Does The Dog Know The Proverb

The little boy did not like the look of the barking dog.
一个小男孩非常不喜欢狗狂叫的样子。
"It's all right," said a gentleman, "don't be afraid. Don't you know the proverb: Barking dogs don't bite?"
“没有关系，”一位先生说，“不用害怕，你知道这条谚语吗：‘吠狗不咬人。’”
"Ah, yes," answered the little boy. "I know the proverb, but does the dog know the proverb, too?"
“啊，我是知道，可是狗也知道吗？”

1.Don't you know
do you know 就是一般疑问句，意思是“你知道。。。吗？”，表示单纯的疑问。
而don't you know是反问句，意思是“难道你不知道。。。吗？”表达的是肯定的意思，用反问的方式加以强调。
例句：
Do you know that she is coming next week?
你知道她下周要来的事情吗？（不确定她下周来不来）
Don't you know that she is coming next week?
你难道不知道她下周要来？（她下周来是确定了的。）

2. Barking dogs don't bite
直译：爱叫的狗不咬人，咬人的狗不露齿。吠犬不咬人。
意译：外强中干。虚有其表。虚张声势。