be lost for words
US /bi lɔst fɔr wɜrdz/
UK /bi lɔst fɔr wɜrdz/

1.
说不出话来, 无言以对
to be so surprised, confused, or emotional that you cannot think of anything to say
:
•
When she saw the surprise party, she was completely lost for words.
当她看到惊喜派对时,她完全说不出话来。
•
His rude comment left me lost for words.
他粗鲁的评论让我说不出话来。