疎い

1. Origins, structure, and basic meaning

• Structure: 疎い is an い-adjective read うとい, describing unfamiliarity or a distant relationship.
• Basic usage: It is used for being unfamiliar with machinery or growing apart from old friends.

2. Common pitfalls and similar expressions

• A field and a relationship
  • In 機械に疎い, に marks the field one is unfamiliar with.
  • 友人とは疎くなる describes growing distant from a friend.
• Form for a change
  • In 疎くなる, the ending of 疎い changes to く before joining なる.