Final answer:
The excerpts that create a dreary mood highlight 'cavernous gloom' and 'fearful darkness', emphasizing the eerie setting in 'The Legend of Sleepy Hollow'.
Step-by-step explanation:
The two excerpts from The Legend of Sleepy Hollow by Washington Irving that create a dreary mood are:
“A few rough logs, laid side by side, served for a bridge over this stream. On that side of the road where the brook entered the wood, a group of oaks and chestnuts, matted thick with wild grapevines, threw a cavernous gloom over it.” and “The road that led to it, and the bridge itself, were thickly shaded by overhanging trees, which cast a gloom about it, even in the daytime; but occasioned a fearful darkness at night.”
These excerpts use descriptions like “cavernous gloom” and “fearful darkness” to evoke the dreary and haunting atmosphere that characterizes the mood of the story.