Helen sat upright in her chair.

海伦笔直地坐在椅子上。

She sat upright in bed.

她挺直地坐在床上。

She sat upright, her body rigid with fear.

她直挺挺地坐着，吓得浑身发僵。

With a swift movement, Matthew Jerrold sat upright.

马修·杰罗德迅速地坐直了。

They sat upright and began slapping the water with their front legs and splashing themselves.

它们坐立起来开始用前腿拍水并向自己身上溅水。