How to make script continue after function?

So lets say I had a script:

local function a()
	wait(math.random(1,5))
	print("This is a function")
end)

while true do
	a()
	wait()
end

With this script, it would wait until our function, a, is complete before running it again. Is there any way that I could make the while loop "ignore" the wait inside the function, and do the next thing immediately?