什么是emergencyflare?新编英语教程第二册Unit04有这个词.请问是什么物质?原文如下（双引号部分）DIALOGUEIIA:Ihearyouoncewentsailing.B:Oh,yes.I'llneverforgetthetimeIborrowedaboatandtriedmyhandatsaili

Question

什么是emergency flare?
新编英语教程第二册Unit04有这个词.
请问是什么物质?
原文如下 （双引号部分）
DIALOGUE II
A:I hear you once went sailing.
B:Oh,yes.I'll never forget the time I borrowed a boat and tried my hand at sailing!It was a terrible experience...
A:Tell me about it.
B:Well,the first two days went marvellously.The weather was perfect and I felt so happy that everything was going smoothly.
A:Then what happened?
B:Well,10 miles off shore,the boat suddenly started letting in water.
A:No!
B:At first I looked around for a bucket or something,but I couldn't find anything.I was in such a panic!
A:What were you doing when the boat started leaking?
B:Well,I was preparing my lunch,but I just had to drop everything.
A:Why hadn't you checked your safety equipment?
B:I know.I ought to have checked it,but I just hadn't.
A:Why didn't you send up an “emergency flare”
B:I should have,but everything happened so fast,and then ...the boat capsized.
A:Oh,no!How awful!
B:Yes,dreadful!You see,I couldn't swim,either!
A:Oh,no!It gets worse!Why didn't you learn to swim when you were younger?
B:I could have had swimming lessons,but I never got round to it somehow.I should have learnt to swim.That's what I kept thinking while I was in the water,before the fishing boat came along.Why didn't I learn to swim?
A:What would you have done if the boat hadn't appeared when it did?
B:Oh,I don't know.I suppose I might have drowned.I don't like to think of the consequences.I could have shouted for help or tried to swim for the shore.I think I could have made it too.

Answer 1

求救的闪弹,就是那种可以对天空发射,发出亮光,可以引起别人注意的闪弹,电视里面求救的时候经常可以看到的.
set up就是发射的意思,