What are they doing?
They are kayaking on the river.
What is he doing?
He is swimming in the lake.
What is he doing?
He is climbing a mountain/ He is rock climbing.
What are they doing?
They are swimming in the sea.
What is he doing?
They are walking in the mountains.
What is she doing?
She is spending time at home. /She is reading.
What is she doing?
She is visiting a city/ She is sight-seeing.
What is she doing?
She is sleeping in the garden.
What are they doing?
They are waling in the forest.