instruction:
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.
question:
Sentence1: With a spatula, fold in flour mixture. 
Sentence2: a sifter is used for separating flour.
answer:
flour


question:
Sentence1: Endocrine glands include the pituitary, thyroid, parathyroid, adrenal, pineal and thymus glands. 
Sentence2: Some pituitary hormones can control the thyroid gland.
answer:
thyroid


question:
Sentence1: Pneumonia may be caused by an infection or injury of the lungs. 
Sentence2: Streptococcus can infect the lungs following injury.
answer:

infection