What are they doing? (ride)
They are riding a (triple tandem) bicycle!
What are they doing? (take)
They are taking a photo (selfie).
What are they doing? (splash)
They are splashing in the pool.
What are they doing? (snorkel)
They are snorkeling.
What are they doing? (take)
They are taking a sightseeing tour.
What are they doing? (camp)
They are (going) camping.
What is he doing? (build)
He's building a sandcastle.
What are they doing? (hike)
They are (going) hiking.
What are they doing? (read)
They are reading (a book).
What are they doing? (play)
They are playing at the beach.
What are they doing? (ride)
They are riding a roller-coaster.
What are they doing? (row)
They are rowing a boat.
What is she doing? (write)
She is writing a postcard.
What are they doing? (sleep)
They are sleeping in bunk beds.
What are they doing? (play)
They are playing volleyball.
What is she doing? (pack)
She is packing a bag (suitcase).
What are they doing? (swim)
They are swimming in the pool.
What are they doing? (fly)
They are flying on an aeroplane.
What is she doing? (take)
She is taking a photo.
What are they doing? (ride)
They are riding a water slide.
What are they doing? (stay at)
They are staying at a hotel.
What are they doing? (eat)
They are eating ice cream.