He stood up straight with arms folded, and laughed at the cap hanging there on the pole.

他交臂直立，笑看帽子挂在杆子上那个样子。

youdao

He finished his conversation and stood up, looking straight at me.

他结束了谈话站起来，直视着我。

《柯林斯英汉双解大词典》

He stood up to get a better view, turned around, and found himself staring straight into the eyes of the answer.

他站起身以便更好地察看，转过头去，一双眼睛正瞪着他。

youdao

Then he stood up straight and responded loudly enough for all the kids to hear.

NPR: Del Close and the Roots of Second City

He stood up and with a straight face said it wouldn't be appropriate for him to give stock tips.

CNN: ASIANOW - TIME Asia