WAEC - English Language (2019 - No. 44)
choose the word or group of words that best completes each of the following sentences:
The trader tried to cash in________the customer's ignorance.
by
at
on
with
Vysvětlení
The completed sentence would be: "The trader tried to cash in on the customer's ignorance."
In this context, "to cash in on" means to take advantage of something, in this case, the customer's ignorance, for personal gain.