YOU SAID:
I gallop across the valley.
INTO JAPANESE
私は谷間を疾走します。
BACK INTO ENGLISH
I gallop through the valley
INTO JAPANESE
谷間を駆け抜ける
BACK INTO ENGLISH
run through the valley
INTO JAPANESE
谷を駆け抜ける
BACK INTO ENGLISH
run through the valley
Come on, you can do better than that.