keep it secret 还是keep it secretly

keep it secret 释义：

保守秘密

例句：

He tried to keep it secret from his family.

这件事他试图瞒着家里。

keep it secretly释义：

保持它的秘密

例句：

Case-dough means that someone has some money secretly and would like to keep it permanently secret， especially he doesn't want his spouse to know it， because he has some purpose.

私房钱指某人偷偷地将钱留起来并希望永远没人知道，尤其不希望他的伴侣知道，因为他是有目的的。