ことだから
Given that it is … / considering the nature or character of … → expresses a natural expectation or judgment based on a person’s known character, habits, or typical behavior
N1
Meaning
Given that it is … / considering the nature or character of … → expresses a natural expectation or judgment based on a person’s known character, habits, or typical behavior
Formation
Noun + の + ことだから + Clause
Clause (plain form) + ことだから + Clause
Explanation
ことだから is used when the speaker makes a reasonable assumption or judgment based on who someone is or what they are like.
🔸 ことだから = expectation based on character
Core logic:
“Because this is that kind of person / situation, this result is to be expected.”
Key nuances:
The judgment is not random
It is based on:
personality
past behavior
reputation
typical tendencies
The conclusion sounds natural and unsurprising
Often used for people, not abstract rules
Tone and usage:
Semi-formal to formal
Common in explanations, narratives, and reasoning
Frequently appears in JLPT N1 reading passages