It was very cold. The snow / lake was very deep and difficult to walk through.
snow
He was climbing the mountain / water for hours; it took a long time to get to the top.
mountain
The farmer was working in the field / cliff all day.
field
She looked over the cliff / island, down to the water / mountain below.
cliff/water
They were sailing on the field / lake when it started to rain.
lake
The mountain / island is 2 km from the mainland. There is a ferry every hour.
island
Is it difficult to swim across the river / snow?
river