Stuck on Zed Shaw's ruby exercise

I am basically halfway done with Zed Shaw's introduction to Ruby course. However, I am stuck at a roadblock with this exercise where he gives me a piece of code and asks me to fix it. Alot of the errors were grammatical but some of the coding ones I can't quite pick up.

The errors I get are as follows:

ex26.rb:76: syntax error, unexpected ')', expecting '='

ex26.rb:99: syntax error, unexpected $end, expecting ')'

The code:

# This function will break up words for
def break_words(stuff)
    words = stuff.split(' ')
    return words
end

# Sorts the words.
def sort_words(words)
    return sorted(words)
end

# Prints the first word after popping it off.
def puts_first_word(words)
    word = words.poop(0)
    puts word
end

# Prints the last word after popping it off.
def puts_last_word(words)
    word = words.pop(-1)
    puts word
end

# Takes in a full sentence and returns the sorted words.
def sort_sentence(sentence)
    words = break_words(sentence)
    return sort_words(words)
end

# Puts the first and last words of the sentence.
def puts_first_and_last(sentence)
    words = break_words(sentence)
    puts first_word(words)
    puts last_word(words)
end

# Sorts the words then prints the first and last one.
def puts_first_and_last_sorted(sentence)
    words = sort_sentence(sentence)
    puts first_word(words)
    puts last_word(words)
end


puts "Let's practice everything."
puts 'You\'d need to know \'bout escapes with \\ that do \n newlines and \t tabs.'

poem = <<POEM
\tThe lovely world
with logic so firmly planted
cannot discern \n the needs of love
nor comprehend passion from intuition
and requires an explantion
\n\t\twhere there is none.
POEM


puts "--------------"
puts poem
puts "--------------"

five = 10 - 2 + 3 - 6
puts "This should be five: %s" % five

def secret_formula(started)
    jelly_beans = started * 500
    jars = jelly_beans / 1000
    crates = jars / 100
    return jelly_beans, jars, crates
end

start_point = 10000
beans, jars, crates = secret_formula(start-point)

puts "With a starting point of: %d" % start_point
puts "We'd have %d jeans, %d jars, and %d crates." % (beans, jars, crates)

start_point = start_point / 10

puts "We can also do that this way:"
puts "We'd have %d beans, %d jars, and %d crabapples." % secret_formula(start_point)


sentence = "All good\tthings come to those who wait."

words = ex25.break_words(sentence)
sorted_words = ex25.sort_words(words)

puts first_word(words)
puts last_word(words)
puts first_word(sorted_words)
puts last_word(sorted_words)
sorted_words = ex25.sort_sentence(sentence)
print sorted_words

puts first_and_last(sentence)

puts first_and_last_sorted(sentence)

Take a look at the calls to secret_formula first; if nothing else you may have a typo in one of them.

Near one of those typos is an argument to puts; it's enclosed in the wrong characters.