2013高考英语备考:set短语用法说明
set off (for)出发,动身(去某地)
set off 引爆
set out to do sth.着手……
n.
set about+ doing开始(着手)做……
①We’ll set off fox Xi’an at six tomorrow.
②Polonium is used to set off a nuclear bomb.
③He set out to break the record for the crosschannel swim...