They have sold their house and … on a tour of the world.
(a) go
(b) went
© gone
(d) going
Question ¹ 1
My friend told me that "going" would be correct.
But my version is © . Am I right?
Question ¹ 2
Can I say:
They have sold their house and [b]have[/b] gone on a tour of the world.
Is the auxiliary "have" optional here?