1、informal or natural; especially caught off guard or unprepared.
非正式的或簡單自然的；特別指毫無戒心或準(zhǔn)備。

2、The children tried to throw their father off guard and got money.
孩子們企圖讓父親放松警惕給他們些錢。

3、He had a way of throwing Helen off guard with his charm when she least expected it.
他有辦法用他的魅力讓海倫在最意想不到的時候失去戒備。

off guard翻譯