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: Sentence 1:A suicide car bomber detonated his bomb as he attempted to drive an SUV into a Somali military camp . Sentence 2:However the vehicle exploded at the entrance when police guards opened fire on the insurgent driving the vehicle .
Example solution: however
Example explanation: The above sentence is connected by the word 'however'.

Problem: Sentence 1:In the above , function ( ) can be called by different threads without any problem . Sentence 2:But , if the function is used in a reentrant interrupt handler and a second interrupt arises inside the function , the second routine will hang forever .

Solution: but