TASK DEFINITION: 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:Extraction of rather small amounts of U-234 from natural uranium would be feasible using isotope separation , similar to that used for regular uranium - enrichment . Sentence 2:However , there is no real demand in chemistry , physics , or engineering for isolating U-234 .

SOLUTION: however

PROBLEM: Sentence 1:Whereas , ad valorem tax appeals can often be made at a local level without any professional help , special assessment appeals often require the assistance of attorneys , engineers and other consultants . Sentence 2:Furthermore , a taxpayer often has the opportunity to protest a property tax assessment annually .

SOLUTION: furthermore

PROBLEM: Sentence 1:They give up on things that they can not do anything about , and do what they can . Sentence 2:However , this does n't mean that they are powerless beings that succumb to reality .

SOLUTION:
however