①through穿过（through是介词，意思是从立体空间穿过，与in有关）:

through the forest穿过森林／through the jungle穿过热带丛林／through the clouds穿过云层／through the tunnel 穿过隧道

He drove through the tunnel.他开车经过了隧道。

They walked through the forest.我们徒步穿过了森林。

②across穿过（across 是介词，意思是从平面上穿过，与on有关）:

across the street穿过大街／across the road穿过马路

He ran across the street.他跑过了大街。

③cross穿过（cross是动词，cross=go across）