(be) a dinosaur
he
(paint) the mona lisa
не
(write) hamlet
they
(be) from scandinavia.
he
(invent) the telephone.
they
(make) their first flight
at kitty hawk, north carolina.
не
(become) the first
astronaut to travel to outer space.
(begin) in 1939
they
(discover) polonium
and radium