Given phrases that describe the relationship between two words/phrases as options, extract the word/phrase pair and the corresponding lexical relationship between them from the input text. The output format should be "relation1: word1, word2; relation2: word3, word4". Options: product/material produced, manufacturer, distributed by, industry, position held, original broadcaster, owned by, founded by, distribution format, headquarters location, stock exchange, currency, parent organization, chief executive officer, director/manager, owner of, operator, member of, employer, chairperson, platform, subsidiary, legal form, publisher, developer, brand, business division, location of formation, creator.
Text: Shares of United over the past five years have generated about half the return of rival Delta Air Lines , and analysts have worried the company is falling behind once-bankrupt American Airlines Group as that company integrates its merger with US Airways Group .
user
parent_organization: US Airways, American Airlines Group; subsidiary: American Airlines Group, US Airways; owner_of: American Airlines Group, US Airways; owned_by: US Airways, American Airlines Group
assistant