Detailed Instructions: In this task, you are given two sentences in the English language (Sentence 1 and Sentence 2). Your task is to identify the connecting word between the two sentences.
Problem:Sentence 1:In 2005 the subway line of the lower part was reopened between Piscinola - Scampia ( interchange with Naples Metro line 1 ) to Mugnano . Sentence 2:Then , in 2009 , it was extended to Aversa .
Solution:
then