Vocabulary consisting only from characters you are able to read
二人
ふたり
two persons, two people, pair, couplejlpt5
中
なか
inside, middle, amongjlpt5
水力
すいりょく
hydraulic power, water powermix
山
やま
mountain, pile, heap, climax, critical pointjlpt5, shizen
上
うえ
above, on top of, up, upper part, surfacejlpt5