随分

1. Origins, structure, and basic meaning

• Structure: The degree adverb 随分 (ずいぶん) means considerably or very, often with a sense that the degree is striking.
• Basic usage: It intensifies duration in 随分長い間 and the scale of change in 随分変わった.

2. Common pitfalls and similar expressions

• A considerable or surprising degree
  • Besides intensifying degree, it can convey that the extent feels greater than the speaker expected.