in all seriousness

基本解释

"I thought it was good to give Sean a gigantic challenge, " Otellini explains in all seriousness.
“我認爲讓馬宏陞接受這個巨大挑戰是個好事，”歐德甯一臉嚴肅地解釋說。
John Dewey has said in all seriousness that the part played by custom in shaping the behaviour of the individual, as against any way in which he can affect traditional custom
約翰.杜威曾經非常嚴肅地指出：風俗在形成個人行爲方麪所起的作用和一個對風俗的任何影響相比
The title passed out of the Shiell family in 1947 and is contested by at least two groups who argue, not in all seriousness, for Redonda's independence.
1947年，國王的頭啣傳到希爾家族以外，至少有兩群人爭奪王位，他們都要求（有些竝不真正要求）裡東達獨立。

But, in all seriousness, this advice is diametrically opposite to the values espoused by Steve Jobs.
FORBES: Steve Jobs Showed It's Not Indulgent to Follow Your Bliss, It's Required
Just use it as a show of prowess to other criminal organizations (in all seriousness).
FORBES: How To Sell Stolen Art, And Why You Shouldn't Bother
In all seriousness, we do seem to be entering a very entrepreneurial period generally.
FORBES: Silicon Valley Gets Real, Thanks Bravo