An Asian woman leaves the deli hand in hand with her black boyfriend, when suddenly, a beggar imposes on them.
Whats wrong with this sentence? Word claims that the grammar is wrong
Hard to tell-- be wary of sentence checks and spell checks: they are notoriously erratic. It is much better to rely on yourself, in the long run.
Probably the comma after 'suddenly' is wrong; I would certainly call it so.