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: Leaves make food for the plant. 
Sentence2: Some producers have leaves to help use energy and inorganic molecules.

SOLUTION: Leaves

PROBLEM: Sentence1: Bees feed on nectar and pollen. 
Sentence2: Plant reproduction often requires bees and nectar.

SOLUTION: Bees

PROBLEM: Sentence1: Placental mammals are therian mammals in which a placenta develops during pregnancy. 
Sentence2: Mammals that are therians house the embryo until it is complete during pregnancy.

SOLUTION:
during