You will be given a definition of a task first, then some input of the task.
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.

Sentence1: An ecosystem includes the organisms and their habitat. 
Sentence2: energy enters organisms and their habitat in the form of sunlight or chemical compounds.
Output:
habitat