stumble over 绊倒在……上
stumble upon 偶然发现
stumble across 偶然遇到
stumble into 不小心进入
stumble and fall 跌跌撞撞
stumble forward 踉跄向前
stumble through 磕磕绊绊完成
A: He always stumbles when he speaks in public.
A：他在公开场合讲话时总是结结巴巴。
B: Yes, but he is improving and stumbling less now.
B：是的，但他正在进步，现在失误少多了。
1) 走路时失去平衡或绊倒
2) 说话或表达时出错、犹豫
3) 在做事情时遇到小失误或阻碍
1. 绊倒；踉跄
verb
1. to hit your foot against something while walking or running and almost fall
Synonym: trip, falter, slip