Panic set off all of the country 里的 set off 不是激起的意思吗》、?应该用被动

为什么不用被动 Panic set off across the whole country. panic set off across the whole country.这句话中是被动语态吗 Panic set off across the whole country.此句中,为什么不用被动语态? set off的意思 panic on the stock makert set off （had set off）a wave of sel set sb off 的意思 The panic set off across the whole country为什么不用though panic set off across the whole country谓语动词为什么不用第三人称单数形式? The panic set off __ country at last.正确答案是C,为什么B不可以? set off的过去式 set off 和 set out 都有出发的意思, set off down的意思是什么?