脇

1. Origins, structure, and basic meaning

• Structure: 脇(わき) is a noun for the armpit or the space immediately beside something.
• Basic usage: 椅子の脇 is the space beside a chair; シャツの脇 is the underarm part of a shirt.

2. Common pitfalls and similar expressions

• Read it with the preceding noun
  • The noun before の脇 helps identify the sense. With the chair it is adjacent space; with the shirt it is the part corresponding to a body area.
• に marks placement
  • In 椅子の脇に置いた, に marks where the bag was placed.