Complex sentence: This is an identity label that people can claim permanently when they understand that there are one or two people they could have a gay or lesbian relationship with, or is sometimes claimed temporarily when they are in a same-sex relationship.
Split into simpler sentences: This is an identity label that people can claim permanently when they understand that there are one or two people they could have a gay or lesbian relationship with. Or it can be claimed temporarily when they are in a same-sex relationship.