拭う

1. Origins, structure, and basic meaning

• Structure: 拭う is read as ぬぐう and is a transitive verb for wiping away sweat or moisture and, figuratively, dispelling mistrust or anxiety.
• Basic usage: Mark the removed object with を in 汗を布で拭う and 不信感を拭う; で marks the cloth used as the tool.

2. Common pitfalls and similar expressions

• Instrumental で
  • 布で identifies the wiping instrument, while 汗を is the substance being removed.
• Degree of figurative removal
  • The metaphor suggests clearing mistrust away, but 難しい states that one apology is not enough to achieve that result easily.