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.

[Q]: Sentence 1:Membership in the FDJ was nominally voluntary . Sentence 2:However , those who did not join lost access to organized holidays , and found it difficult ( if not impossible ) to be admitted to universities , pursue chosen careers etc .
[A]: however

[Q]: Sentence 1:Archeops flew for the first time in Trapani ( Sicily ) with four -- hours integration time . Sentence 2:Then , the upgraded instrument was launched three times from the Esrange base near Kiruna ( Sweden ) by the CNES during 2 consecutive Winter seasons ( 2001 and 2002 ) .
[A]: then

[Q]: Sentence 1:From the definition , it is also clear that large optical depths correspond to higher rate of obscuration . Sentence 2:Optical depth can therefore be thought of as the opacity of a medium .
[A]:
therefore