Kànzhe hé lǐ zhēngzhá de rén, lùrén què gǒngshǒupángguān.
Watching the person struggle in the river, passersby stood by doing nothing.
Tips
memory
拱手 = clasp hands in a salute (so they're occupied), 旁观 = watch from the side. Together: hands tucked in your sleeves while you watch — i.e. doing nothing. Near-synonym 袖手旁观 (xiùshǒupángguān) is more common.