Hi, Does "trend" here is a noun mass? If not, it is a bit strange because there is not one trend in the studying...

"In studying the trend in international politics, scholars have come up with analytical concepts that help to understand this complex phenomenon"
Is it a mass noun? No, I don't think so.

I think that they are talking about one specific trend (hence the "the" before trend).
Hi Ivan, I see but they don't refer to "the" in the rest of text I will have to look on the text again, so for now I understand trend here as "singular trend" thanks...
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I assume the trend was mentioned previously in the text (they didn't have to use the word trend at all; any phrase that could have been interpreted as "trend" would suffice) .

I'm starting to think they refered to something in general, only to learn x trend in international politics, if you want to take a look in the article.

I didn't read through the whole text but, as far as I can tell, "the trend" refers to the current trend in international politics (whatever the current trend is).
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Yes this is the same conclusion I arrived in the end, thanks Emotion: smile