I can endorse their opinion wholeheartedly.

我可以全心全意地支持他们的观点。

《柯林斯英汉双解大词典》

I wholeheartedly endorse his remarks.

我真诚地赞同他的话。

《牛津词典》

This is a sentiment I wholeheartedly agree with.

这种态度我完全赞同。

《牛津词典》

NATO has nearly 60,000 troops in Afghanistan, but few alliance members wholeheartedly support the deployment, with many questioning what the North Atlantic alliance is doing there in the first place.

VOA: standard.2009.07.27

So, so many people loved Junie, and she returned that love, wholeheartedly, unconditionally, non-judgmentally, beautifully.

FORBES: My Aunt, Olive June Black, An Ohio Original -- In Memoriam

It was clear that not all of the guests were wholeheartedly committed to the cause.

NEWYORKER: The Hardest Vote

After the murders at Sandy Hook school he wholeheartedly embraced the cause of greater gun control.

BBC: Obama as warrior and healer