stolid

尽管听到坏消息，他仍然面无表情地站在那里。

Despite hearing the bad news, he stood there with a ___stolid expression.

教官在他脸前几英寸处吼叫，这名士兵却岿然不动。

The soldier remained ___stolid as the drill sergeant shouted inches from his face.

急诊室护士在同时分诊三名危重病人时，神情始终沉稳。

The emergency room nurse kept a ___stolid face while triaging three critical patients at once.