What is wrong with this script?[Not answered]

Am I missing something?

local function weldBetween (a,b)
	local weld = Instace.new ("ManualWeld")
	weld.Main = a----Part 1
	weld.Part1 = b----Part 2
	weld.C0 = Cframe.new()---Determines how offset the first part should be 
	weld.C1 = b.Cframe:Inverse() *a.Cframe ---* moves do the cframe
	weld.Parent = a
	return weld;
	
	
end

weldBetween (game.Workspace.Drone.Main, game.Workspace.Drone.Part1

Try this:

local function weldBetween(a,b)
	local weld = Instance.new("Weld")
	weld.Part0 = a
	weld.Part1 = b
	weld.C0 = CFrame.new()
	weld.C1 = b.CFrame:inverse()*a.CFrame
	weld.Parent = a
	return weld;
end

weldBetween()--[[put where you want the weld to be between in these ()
example: weldBetween(game.Workspace.weldExample1, game.Workspace.weldExample2)
they both are parts btw --]]