Roblox Script Generated by ScripterAI

"Write me a script that capitalizes the beginning of a sentence and adds punctuation based on what the player says, like if they ask a question or say something in general."

```lua
-- Local Script
local Players = game:GetService("Players")
local ChatService = game:GetService("Chat")

local function capitalize(str)
    return str:sub(1, 1):upper() .. str:sub(2)
end

local function addPunctuation(str)
    local lastChar = str:sub(-1)
    if lastChar ~= "." and lastChar ~= "?" and lastChar ~= "!" then
        str = str .. "."
    end
    return str
end

local function onPlayerChatted(player, message)
    local capitalizedMessage = capitalize(message)
    local punctuatedMessage = addPunctuation(capitalizedMessage)
    ChatService:Chat(player.Character.Head, punctuatedMessage, Enum.ChatColor.Blue)
end

Players.PlayerAdded:Connect(function(player)
    player.Chatted:Connect(function(message)
        onPlayerChatted(player, message)
    end)
end)
```
This script will capitalize the first letter of a player's message and add punctuation if it's missing. It will then display the modified message above the player's head. Note that this is a local script and should be placed in a suitable location, such as StarterPlayerScripts.