Countable:
* Specific bills: When referring to individual pieces of paper money, "bill" is countable.
* Example: "I have a five-dollar bill in my pocket."
* Example: "She paid with two twenty-dollar bills."
* Specific bills (as in documents): When referring to individual invoices, "bill" is countable.
* Example: "I need to pay all my bills before the end of the month."
* Example: "The restaurant gave us a separate bill for the drinks."
Uncountable:
* General concept of money: When referring to money in general, "bill" is uncountable.
* Example: "He doesn't have much bill." (Meaning: He doesn't have much money)
* Example: "The company pays all its employees' bills." (Meaning: The company pays all the expenses of its employees)
To determine whether "bill" is countable or uncountable in a specific sentence, consider the context and the meaning.