Mouse Position over a block and key is pressed not working?

This script must be in a LocalScript inside the player for this to work. Placing this script in StarterGui would allow this to work.

Mouse = game.Players.LocalPlayer:GetMouse() --You need to set a variable for the actual Mouse. You cannot just say "Mouse". This sets the player's mouse as the variable "Mouse".

function keyDown(key)
    if Mouse.Target == workspace.Part1 then --Place this if statement inside of the function so it will run whenever the player presses z. If you place it outside, it will check it right when you join the game instead of when you press z. Also, Mouse.Target is a better property than Mouse.Position because it refers to the entire block on the screen, not the exact center.
    if string.lower(key) == "z" then --string.lower in case they're in caps lock or something.
--preform action
    end --Ends the if statement.
end  --Ends the other if statement.
end --Ends the function.

Mouse.KeyDown:connect(keyDown) --Connects the function to the mouse using the event KeyDown so when you press "z", the script actually does something.

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