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.

[Q]: Sentence1: Dromaeosaurs are part of the theropod group of dinosaurs.
Sentence2: Birds evolved from a group of bipedal dinosaurs that included Dromaeosaurs.
[A]: Dromaeosaurs

[Q]: Sentence1: Acid rain is precipitation which pH is 5.7 or lower.
Sentence2: gases from burning coal causes precipitation which pH is 5.7 or lower.
[A]: 5

[Q]: Sentence1: And somewhere a beagle howls a most pitiful sound.
Sentence2: wolves use sound to warn other wolves.
[A]:
sound