TASK DEFINITION: Generate an overlapping word between the given two sentences. When you find the overlapping words, they don't have to match exactly, e.g., "survival" and "survive" are valid overlapping words. Little words like "the" or "of" don't count! You must generate significant words which are not the stop words.
PROBLEM: Sentence1: when a river floods , that river deposits soil in flood plains. 
Sentence2: when a river floods, it deposits soil in generally marshy areas.

SOLUTION: deposits

PROBLEM: Sentence1: Insect wings are attached to the dorsal side of their thorax. 
Sentence2: wings are attached to the dorsal side of the insect.

SOLUTION: dorsal

PROBLEM: Sentence1: An atoll is the third type of reef. 
Sentence2: Atolls are built by corals secreting an exoskeleton.

SOLUTION:
atoll