set off firecrackers是什么意思?

In many places people like to set off firecrackers .是什么意思 We always set off firecrackers 0:00 a.m. firecrackers是什么意思 what excites us most is that we can set off firecrackers whe ______,we set off firecrackers on New Year's Eve to frighten set off是什么意思啊? set off 是什么意思啊? set out set away set aside set off 请问 都是什么意思? set off fireworks和let off fireworks是什么意思? set out,set up,set off,set set out与set off set aside set down set off