fly-by-night - a person or company as fly-by-night means they are unreliable and irresponsible, and their work is probably not of good quality. 不可靠的
You can’t trust that company, because they’re a fly-by-night operation.
你不能相信那家公司，因为他们是一个不可靠的公司。
fly in the face of sth - to completely oppose what seems sensible or normal 公然冒犯
This is an argument that seems to fly in the face of common sense.
这似乎是一个违背常识的观点。
It flies in the face of everything I have been taught.
它与我所学的一切背道而驰。
fly off the handle/fly into a rage - to react in a very angry way to something that someone says or does. 勃然大怒
He’s extremely irritable, and he flies off the handle at the slightest thing.
他非常暴躁，一点小事就发火。
He flew into a rage when I told him you were not giving his money back.
当我告诉他你不还他的钱时，他勃然大怒。
on the fly - without previous planning; 没有计划做某事
I don’t have enough time to prepare, so I guess I’ll just have to do in on the fly.我没有足够的时间准备，我想我只能匆匆忙忙地做了。
You know, his speeches are much better when he does them on the fly.你知道，如果他好好准备的话，他的演讲会更好。
a flying start - a very good start to something, quickly making good progress. 良好的开端
She’s got off to a flying start in her new job.
她在新工作中有了一个良好的开端。
He got off to a flying start in the race.
他在比赛一开始就表现出色。
Babe_Jasmine
fly-by-night - a person or company as fly-by-night means they are unreliable and irresponsible, and their work is probably not of good quality. 不可靠的 You can’t trust that company, because they’re a fly-by-night operation. 你不能相信那家公司，因为他们是一个不可靠的公司。
Babe_Jasmine
fly in the face of sth - to completely oppose what seems sensible or normal 公然冒犯 This is an argument that seems to fly in the face of common sense. 这似乎是一个违背常识的观点。 It flies in the face of everything I have been taught. 它与我所学的一切背道而驰。
Babe_Jasmine
fly off the handle/fly into a rage - to react in a very angry way to something that someone says or does. 勃然大怒 He’s extremely irritable, and he flies off the handle at the slightest thing. 他非常暴躁，一点小事就发火。 He flew into a rage when I told him you were not giving his money back. 当我告诉他你不还他的钱时，他勃然大怒。
Babe_Jasmine
on the fly - without previous planning; 没有计划做某事 I don’t have enough time to prepare, so I guess I’ll just have to do in on the fly.我没有足够的时间准备，我想我只能匆匆忙忙地做了。 You know, his speeches are much better when he does them on the fly.你知道，如果他好好准备的话，他的演讲会更好。
Babe_Jasmine
a flying start - a very good start to something, quickly making good progress. 良好的开端 She’s got off to a flying start in her new job. 她在新工作中有了一个良好的开端。 He got off to a flying start in the race. 他在比赛一开始就表现出色。