# Module:Grammar/Conjugate

```local p = {}

function p.pluralize(str, apostrophe)
apostrophe = apostrophe or ''
local irregularplurals = {
Man = 'Men',
man = 'men'
}
if irregularplurals[str] ~= nil then
return irregularplurals[str]
elseif (string.find(str, ' of ')) then
i = string.find(str, ' of ')
return p.pluralize(string.sub(str, 1, i-1)) .. string.sub(str, i)
elseif (string.find(str, ' with ')) then
i = string.find(str, ' with ')
return p.pluralize(string.sub(str, 1, i-1)) .. string.sub(str, i)
elseif (str:sub(-1) == 's') then
return (str .. apostrophe)   --return unmodified (ends with 's', like 'boots', so we shouldn't append another 's')
elseif (string.sub(str, -2) == 'ey') and apostrophe == '' then
return (str .. 's')   --for example, "lamprey"
elseif (string.sub(str, -1) == 'y') and apostrophe == '' then
return (string.sub(str, 1, -2) ..  'ies')
elseif (string.sub(str, -3) == 'ife') and apostrophe == '' then
return (string.sub(str, 1, -4) .. 'ives')
elseif (str:sub(-1) == 'z' or str:sub(-2) == 'ch' or str:sub(-2) == 'sh' or str:sub(-1) == 'x') and apostrophe == '' then
if (str:sub(-6) == 'vortex') then  --special case, capitalize vortex the same way the game does in in-game text like Quantum Jitters description
return (string.sub(str, 1, -3) .. 'ices')
end
return (str ..  'es')
else
return (str.. apostrophe .. 's')
end
end

function p.make_possessive(string)
return p.pluralize(string, "'")
end

function p.singularverb(string)
--[ Assumes the input string is already a plural verb.]
local irregularsingulars = {
["are"] = 'is',
["were"] = 'was',
["have"] = 'has',
["'re"] = "'s",
["don't"] = "doesn't",
["'ve"] = "'s",
["do"] = "does"
}
local result = irregularsingulars[string]
if result ~= nil and result ~= '' then
return result
else
return string .. "s"
end
end

function p.capitalize(str)
return str:gsub("^%l", string.upper)
end

return p
```