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.

"We think 3D printing is a significant long-term opportunity, but the technology is immature in terms of speed, quality and reliability, which has caused problems for Stratasys and 3D Systems," Milunovich wrote.

Answer: product_or_material_produced: Stratasys, 3D printing; industry: Stratasys, 3D printing