Assertion: whale's migration | /r/HasProperty | lengthy
Facets:
Source sentences:
text: They often spend summers feeding in polar waters and undertake lengthy migrations towards the Equator as winter arrives.
text: The gray whale undertakes a lengthy annual migration between its breeding grounds in the south and feeding grounds in the north.
text: They generally spend summers feeding in polar waters and undertake lengthy migrations towards the Equator as winter arrives.