不然我和爷爷怎么能出去
“Otherwise, how could Grandfather and I go out?”
THE DIALOGUE REEL
还允许我们自由出入瀚海山脉
“and allowed us to travel freely in the Hanhai Mountains.”
不然 我和爷爷 怎么能 出去
“Otherwise, how could Grandfather and I go out?”
少君
“Young Master,”
“Be realistic; without this concession, my grandfather and I would be trapped here forever.”
Using a rhetorical question with '怎么能' (how could...) is a standard Chinese conversational strategy to assert logical necessity and fend off criticism.
LEARNING CHUNKS & PARTICLES
otherwise; if not
Commonly placed at the beginning of a clause to introduce the negative consequence that would happen if the premise were false.
how could...; how is it possible to...
Used in rhetorical questions to emphasize impossibility or incredulity.