A. so difficult a work B. such a difficult work C. so difficult work D. such difficult work
A. if B. while C. unless D. As
A. / B. and C. but D. Therefore
As if B. if C. As D. Although
A. although B. as C. while D. When
A. However the story is amusing B. No matter amusing the story is C. However amusing the story is D. No matter how the story is amusing
As long as; to do B. If; to C. Unless; to D. On condition that; doing so
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