This is the 7086th most frequent Japanese word.
リス
Squirrel.
Here, 'リス' is used as a noun referring to a squirrel, the subject of the action described in the sentence.
リスは木の上で遊んでいます。
The squirrel is playing on the tree.
In this sentence, 'リス' is the first item in the list of animals mentioned, showing its role as a subject or participant in the context.
リスとウサギは森に住んでいます。
The squirrel and the rabbit live in the forest.
'リス' acts as the object of the verb '見ました' (saw), indicating what was seen in the situation described.