目瞪口呆 -------- be tongue-tied

例句：
A: What's wrong with her after riding the roller coaster?
坐完过山车后，她怎么啦？
B: She was frightened to be tongue-tied.
她被吓得目瞪口呆。

同义词：
look for grape-seed
lose one's tongne
struck dumb
stunned and speechless