stumbling block 障碍
stumbling upon 偶然发现
A: Is he okay? He is stumbling.
A：他没事吧？他走路踉踉跄跄的。
B: He just tripped on the rug.
B：他刚才被地毯绊了一下。
1) 蹒跚地，踉跄地
2) 偶然发现
3) 绊倒
1. 蹒跚，踉跄
participle
1. Walking or moving unsteadily, as if about to fall.
Synonym: staggering, tripping