[Grammar] long/length?

[bahar57]

Dear All,

In the following sentence which word should be used: length or long?
"The X River with approximately 30 km long/length originates from the northern parts of Y Mountain."

Thank you.
Bahar
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[konungursvia]

It's too poor a sentence to say.

 

[emsr2d2]

Perhaps "The X river, which is 30km long, starts somewhere in the north of Y mountain". Having said that, rivers don't usually start in mountains and we don't usually refer to the north/south/east/west of a mountain, only of a mountain range. We might use the north/south/east/west face of an individual mountain.

 

[Skrej]

I agree with most of what emrs suggests, although I'd argue that actually many rivers do originate in mountains, either from springs or snow-melt.

You could say any of these:

The X River, which is 30 km long, originates in the northern Y Mountains.
The X River, which is 30km in length, originates in the northern Y Mountains.
The X River, with a length of 30 km, originates in the northern Y Mountains.

In all of these examples however, 'Mountains' actually refer to a mountain range, as emrs mentioned, such as the 'Rocky Mountains'.