当她在桌前坐下时，却发现自己不知道该说些什么了。When she sat down at her desk she found that the words evaded her.坐下时我的腿还会痛。My leg still aches when I sit down.他的滑雪板交叉在一起坐下时,姿势很不雅观.His skis crossed and he sat down in a most undignified manner....