I tell you this in all seriousness.

我是严肃地告诉你这件事的。

I tell you this in all seriousness.

我严肃地告诉你这事。

In all seriousness though, I'm curious about the reasoning behind this change.

尽管这应该是个严肃的问题，我还是很好奇这个改动背后的原因。

In all seriousness though, we have met some awesome guys since being picked up by Nihilum.

严肃来说，我们在你黑老母见到了些很棒的家伙。

But in all seriousness we want our best players to stay, and Ronnie falls into that category.

郑重地说，我们希望我们所有最好的球员都能留下，罗尼(罗纳尔多)也是一样。