Musical notation was conceived for the C major scale and each line and space represents a note in this scale.

乐谱为C大音阶而构思，在这个音阶中的每一个线和间都代表一个音符。

《柯林斯英汉双解大词典》

For example, to the occupants of the shuttle orbiting the Earth, it can look like they're traveling on a straight line through space.

例如，对于环绕地球的航天飞机内的宇航员而言，他们似乎是以直线方式在太空中运行的。

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How many lines are there? There's the first line, the second line, but then there's a line of negative space that runs between them. See it?

纸上有几条线？第一条、第二条，但是这两条线之间的空间也是一条线，看到了吗？

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So this line here declares a variable, just storage space called "x" and it's of type "int," which means an integer has to go in it.

这里的这条线声明了一个变量，一个叫做“x“的存储空间，它的类型是“int“,意思是里面存储的是整数型的数据。

哈佛公开课 - 计算机科学课程节选

This exploits one of the predictions of Einstein's general theory of relativity: that the path of a beam of light (which is a straight line in empty space) is bent inwards by the gravity of a massive object.

ECONOMIST: Cosmology: I spy with my little gravitational lens | The

And last year, European aerospace giant EADS announced plans for its Astrium space division to develop a line of suborbital jets to satisfy a space tourism market that it predicts could grow to as many as 15, 000 passengers a year by 2020.

CNN: Opening the space frontier, one tourist at a time

This summer marked the opening of High Line Park, a green space on top of an old elevated railroad trestle.

FORBES: Would you pay $5 for a tour of my apartment?