Let your countenance be pleasant but in serious matters somewhat grave.

面部表情要令人愉快，不过在严肃的场合，表情要庄重。

youdao

When someone insults you, do not let your countenance betray your annoyance.

受到别人侮辱时，不要立即表露在脸上。

youdao

I judged by your countenance, Sir, which was troubled when you said the suggestion had returned upon you.

我是根据你说产生这种联想的时候你脸上不安的表情来判断的。

youdao

To say thank you for all of the blessings that have been showered upon your grateful and smiling countenance?

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