Usage patterns
〈事〉に適切に対応するto respond appropriately to something
It's important to respond appropriately when a problem occurs.
適切な〈物〉を選ぶto choose an appropriate thing (word, method, etc.)
You need to choose appropriate words depending on the situation.
適切な処置を取るto take appropriate measures
The doctor took the appropriate measures.
適切さを欠くto lack appropriateness
The remark was criticized for lacking appropriateness.