being a chinese native, when i saw the word 茫然无措, i totally understood its meaning. but to me, i've never and i think i will never use this expression in my writing or speaking, and i don't think it's a common expression in mandarin. 不知所措 is a nice 成语 which you should memorize; 茫然 is a nice word too. :-)

There is a remote difference. "没有你不知所措施" shows someone is alarmed; and "没有你茫然无措" tells us someone is lost and mazing. :)

Hello 伊丽莎白 エリザベス 엘리자베스, They are both idioms expressing the same state of loss and confusion that the guy suffers " lost without you". 没有你不知所措 means not knowing what to do ,being at one's wit end , embarrassed and at a complete loss. 没有你我茫然无措 This idiom means as well being at one's wit end, can't figure out what to do.

The two expressions sound no difference to me, except 不知所措 seems more commonly used, which literally means 'don't know what to do'. 茫然无措 is like the kind of expression people impulsively made up. To be honest, most Chinese translations of English lyrics are so bad. I even found that in one song 'The Holy Ghost' is translated as 'a halloween gift'. Shocking!!! Another example, a song titled 'Copycat' is translated as 'copy a cat'. I really don't know what the translator was thinking! The Chinese translation of orignal English text is really not a advisable way to study Chinese. Trust me.