Sets a reference point as the backdrop, then makes a claim about something measured against it.
框 · Frame
跟/和 [reference] 比起來, [subject] [claim]
觸 · Trigger
You want to weigh something against a backdrop, then say what stands out.
序 · The move
1Open with 跟 or 和 and name the reference — the backdrop you measure against.Is this the thing held fixed, not the thing you want to say something about?
2Close the bracket with 比起來 and a pause (comma).Does 起來 sit right after 比, lifting the comparison into view?
3After the comma, state the subject and the claim about it.The new point sits outside the bracket, not inside it.
例 · Examples
1跟with / compared to在國內讀書studying within the country比起來weighed against it，出國留學going abroad to study是更大的挑戰is a bigger challenge。
Compared with studying at home, studying abroad is a bigger challenge.
界 · Boundary
A比B
A比B ranks two items on one bare quality (弟弟比哥哥高). 跟…比起來 frames a backdrop, then makes a free-standing claim about the other side. Direct ranking vs framed setup.
跟…一樣
跟…一樣 says the two match. 跟…比起來 weighs them and the claim that follows usually marks a difference. Equality vs measured-against.
跟在國內讀書比，出國留學更大的挑戰 → 跟在國內讀書比起來，出國留學是更大的挑戰 (close the bracket with 比起來, not bare 比)
出國留學比起來跟在國內讀書 → 跟在國內讀書比起來，出國留學… (the reference goes inside 跟…比起來; the subject comes after the comma)
跟在國內讀書比起來出國留學是更大的挑戰 → 跟在國內讀書比起來，出國留學是更大的挑戰 (a comma closes the frame before the claim)
English fronts 'compared with X' and runs straight into the clause. Chinese keeps the reference wrapped between 跟/和 and 比起來, then breaks at a comma before the claim begins.