To say I had lost the thread is putting it mildly.

说的委婉一点，我失去了头绪。

youdao

Putting it mildly, you have caused us some inconvenience.

说温和些，你给我们造成了一些不便。

youdao

To say that Americans do not get value for money is putting it mildly.

要说美国人没有做到物有所值还是客气的。

youdao

To say that many questions remain about the Spark EV is putting it mildly.

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To say OpenStack has been getting a lot of attention lately would be putting it mildly.

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To say it has been a wild day might be putting it mildly.

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