This is the 8191st most frequent Japanese word.
川中
"川中" means "in the middle of a river."
The term '川中' refers to the location 'in the middle of the river,' here used to describe where the small fish are.
川中の小魚は泳ぎ回っています。
The small fish in the middle of the river are swimming around.
In this sentence, '川中' implies a place, 'the middle of the river,' where the family engaged in activities.
家族で川中に行って遊びました。
Our family went to the middle of the river and played.
Here, '川中' describes the specific location 'in the middle of the river,' where the bridge is situated.