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.

Example Input: Sentence 1:When Toothy is drilling , the drill 's battery goes dead , much to his disappointment . Sentence 2:However , after Toothy managed to get another battery .
Example Output: however

Example Input: Sentence 1:The diagnosis of RA was formerly based on detection of rheumatoid factor ( RF ) . Sentence 2:However , RF is also associated with other autoimmune diseases .
Example Output: however

Example Input: Sentence 1:Sandra , for the first time during her career , now participated actively in composing and writing the album . Sentence 2:Therefore , the lyrics of the songs are more personal , with Sandra revisiting her childhood and all her sad experiences in them .
Example Output:
therefore