文件内容rolling.txt:

There's a fire starting in my heart

我怒火中烧

Reaching a fever pitch and it's bringing me out the dark

熊熊烈焰带我走出黑暗

Finally, I can see you crystal clear

最终 我将你看得一清二楚

Go ahead and sell me out and I'll lay your ship bare

去吧 出卖我 我会让你一无全部

See how I'll leave with every piece of you

看我怎么离你而去 带走你的一切

Don't underestimate the things that I will do

不要低估我将来的所作所为

There's a fire starting in my heart

我怒火中烧

Reaching a fever pitch and it's bring me out the dark

熊熊烈焰带我走出黑暗

The scars of your love remind me of us

你的爱情伤痕让我想起了我们曾经的甜蜜

They keep me thinking that we almost had it all

它们总在提醒我 我们几乎拥有了一切

The scars of your love, they leave me breathless

你的爱情伤痕 让我窒息

I can't help feeling

我不禁心生感触

We could have had it all

我们本该拥有一切

(You're gonna wish you never had met me)

(你会祈祷 要是从未遇见我该有多好)

Rolling in the deep

内心深处爱恨交织

(Tears are gonna fall, rolling in the deep)

(眼泪快要掉下来，内心深处爱恨交织)

You had my heart inside your hand

你俘虏了我的芳心

(You're gonna wish you never had met me)

(你会祈祷 要是从未遇见我该有多好)

And you played it to the beat

但是你玩弄它 伴着每一次心跳

(Tears are gonna fall, rolling in the deep)

(眼泪快要掉下来，内心深处爱恨交织)

Baby, I have no story to be told

宝贝 我没有故事可讲

But I've heard one on you and I'm gonna make your head burn

但是我听说了一件有关你的事情 我会让你焦头烂额

Think of me in the depths of your despair

在绝望的深渊中想起我

Making a home down there as mine sure won't be shared

就在那里安家吧 因为我的家园绝对没你的份

The scars of your love remind me of us

你的爱情伤痕让我想起了我们曾经的甜蜜

(You're gonna wish you never had met me)

(你会祈祷 要是从未遇见我该有多好)

They keep me thinking that we almost had it all

它们总在提醒我 我们几乎拥有了一切

一行行的读取文件前5行

第一种方法：

for i in range(5):

print(f.readline().strip())

第二种方法：

line_nu = 0#计数器

for line in f:#一行行的把数据从硬盘加载到内存里读出来

if line_nu<5:#读取前五行

print(line.strip())

line_nu += 1

else:

break

最简单的两种方法。