A fast walk/run on hilly terrain, a fast bike ride (with a helmet!
A fast walk/run on hilly terrain, a fast bike ride (with a helmet!
在起伏的小山坡上来个竞走或小跑，一段赛车（记着带头盔！）
A fast walk/run on hilly terrain, a fast bike ride (with a helmet!
在起伏的小山坡上来个竞走或小跑，一段赛车（记着带头盔！）