They (is/ isn't/ are/ aren't) diving
are
He (is/ isn't/ are/ aren't) diving
isn't
They (is/ isn't/ are/ aren't) windsurfing
aren't
He (is/ isn't/ are/ aren't) surfing
is
He (is/ isn't/ are/ aren't) sailing a boat
is
She (is/ isn't/ are/ aren't) swimming
is
They (is/ isn't/ are/ aren't) sailing a boat
are
She (is/ isn't/ are/ aren't) windsurfing
isn't
He (is/ isn't/ are/ aren't) kayaking
isn't
He (is/ isn't/ are/ aren't) swimming
isn't
They (is/ isn't/ are/ aren't) snorkeling
are
He (is/ isn't/ are/ aren't) waterskiing
is
She (is/ isn't/ are/ aren't) reading a book
isn't
They (is/ isn't/ are/ aren't) surfing
aren't