In context, which would be the most effective way to revise and combine sentences 3 and 4 (reproduced
below)?
He taught himself to juggle. He could juggle three balls perfectly by the age of six.
O to juggle and by the age of six could juggle three balls perfectly.
O to juggle; he juggles three balls perfectly by the age of six.
O to juggle three balls perfectly; they did it by the age of six.
O juggling, and they juggled three balls perfectly by the age of six.