Tickets left

A small venue puts a line under each event on its website saying how many tickets are still available. The site hands your function the name of the event and a count, and wants one line of text back.

Write posterLine, which returns the event name, a colon, a space, the count, and the words tickets left.

Worked example

Input:  event = "Jazz Night", left = 4
Output: "Jazz Night: 4 tickets left."

Input:  event = "Film Club", left = 12
Output: "Film Club: 12 tickets left."

Constraints

• event is between 0 and 60 characters long.
• left is between 0 and 5000.
• The wording never changes. Even when a single ticket is left the line reads 1 tickets left., and with none left it reads 0 tickets left. Fixing the grammar needs a tool you have not met yet.
• If the event name is empty, the line still starts with the colon: ": 7 tickets left."