A few days after his collapse he was sitting up in bed.

他病倒后过了几天就在床上起身坐着了。

《柯林斯英汉双解大词典》

Sue was sitting up in bed, looking very fetching in a flowered bedjacket.

她挺身坐在床上，穿着印花睡衣，看起来很迷人。

《柯林斯英汉双解大词典》

She started sitting up.

她开始坐起来。

youdao

He was still sitting up in the bed listening -- just as I have done, night after night.

VOA: special.2009.05.16

I think even if you're in a chair, and you're sitting up straight with good posture, maybe hands on knees.

哪怕只是坐在椅子上，坐直并保持良好姿势，也许双手放在两膝上。

普林斯顿公开课 - 人性课程节选

Now, I want to ask a question that we're going to need to think about, the two of you sitting up front here, when I was asking you how you responded to it. Can we have a moral response to this novel?

现在，我想要问你们一个我们将要思考的问题，就你们俩吧，坐在前面的，当我问你们如何回应,我们可以对这部小说有一个道德反思吗？

耶鲁公开课 - 1945年后的美国小说课程节选

At 6 months, Calvin wasn't meeting developmental milestones such as rolling over or sitting up.

WSJ: Making Gene Mapping Part of Everyday Care

When they reached the home, they found Jacob sitting up in his patio chair.

NEWYORKER: Deniers

Sitting up one night, in the throes of jet lag, I tried to assign words to it.

WSJ: Getting There in L.A.