总统因病无法履职后，副总统接管了所有职责。

The vice president ___assumed all duties when the president became unable to serve.

他假装若无其事地走进房间。

He ___assumed an indifferent look as he walked into the room.

在表演中，她饰演了一位严厉的老师。

In the play, she ___assumed the role of a strict teacher.

我未经确认就认为会议取消了。

I ___assumed the meeting was canceled without checking.