I was using the "Zilal's Beginner Tutorial" and it came up with this error:

mob
icon = 'person.dmi' //make it so all mobs will be created with the person icon

bug //new prototype
icon = 'bug.dmi' //override the parent's icon, which was 'person.dmi'
var
HP = 30 //define a new variable called HP, with a value of 30

Login()
icon_state = gender //when a player logs in, get them the right icon state for
..() //the gender of their key. Then call the parent!

proc
DeathCheck()
if (HP <= 0)
world << "[src] dies!"
del(src) //delete whatever just died


verb
attack(M as mob in oview(1))
if (M.HP <= 0) //if M's HP are at or below 0...
usr << "[M] is already dead!"
else //otherwise...
usr << "You attack [M]!"
oview() << "[usr] attacks [M]!"
var/damage = rand(1,10)
world << "[damage] damage!"
M.HP -= damage
M.DeathCheck()

say(msg as text) //what the usr says is passed into "msg" as text
world << "[usr]: [msg]" //the world sees chatroom-like output

turf
grass //define a "grass" prototype, which is a kind of turf...
icon = 'grass.dmi' //that has an icon named 'grass.dmi'. In single quotes!

world //we set one of our world's characteristics:
turf = /turf/grass //its default turf is the grass turf.