3 sentences

1. 他在此刻屏营而立，不知所措。

   tā zài cǐ​kè bīng​yíng ér lì, bù​zhī​suǒ​cuò.

   At that moment, he stood there in a state of agitation, not knowing what to do.

   Source: Dong Chinese Dictionary

2. 突如其来的变故让他不知所措。

   tū​rú​qí​lái de biàn​gù ràng tā bù​zhī​suǒ​cuò.

   The sudden change left him at a complete loss for what to do.

   Source: Dong Chinese Dictionary

3. 面对众人的赞扬，他感到有些不知所措。

   miàn​duì zhòng​rén de zàn​yáng, tā gǎn​dào yǒu​xiē bù​zhī​suǒ​cuò.

   He felt a bit overwhelmed by the praise from everyone.

   Source: Dong Chinese Dictionary