This document summarizes Stephen Krashen's Monitor Model Theory of second language acquisition, which includes five main hypotheses: 1) The Acquisition-Learning Hypothesis distinguishes between subconscious language acquisition and conscious language learning. 2) The Natural Order Hypothesis claims language is acquired in a predictable order regardless of teaching. 3) The Monitor Hypothesis describes the role of learned grammar rules in monitoring spoken output. 4) The Input Hypothesis states that language is acquired through comprehensible input at one's current level. 5) The Affective Filter Hypothesis proposes positive affect leads to more language acquisition by lowering the mental block to input.

1. The Monitor Model Theory
1. Acquisition-Learning Theory
2. Monitor Hypothesis
3. Natural Order Hypothesis
4. Input Hypothesis
5. Affective Filter Hypothesis
Stephen Krashen

2. Acquisition-Learning Hypothesis
• Acquisition is a sub-conscious process, as in
the case of a child learning its own language
or an adult 'picking up' a second language
simply by living and working in a foreign
country.
• Learning is the conscious process of
developing a foreign language through
language lessons and a focus on the
grammatical features of that language.

3. Acquisition-Learning Hypothesis
• According to Krashen learned language cannot
be turned into acquisition. It is pointless
spending a lot of time learning grammar rules,
since this will not help us become better users
of the language in authentic situations. At
most, the knowledge we gain about the
language will help us in direct tests of that
knowledge or in situations when we have time
to self-correct, as in the editing of a piece of
writing.

4. Acquisition-Learning Hypothesis
• Gass and Selinker (1994) criticize this hypothesis.
They claim that it does not show evidence of the
distinction between acquisition and learning as
two separate systems.
• However, Krashen said that many can produce
language fluently without having been taught
any rules and there are many that know the
rules but are unable to apply them whilst
speaking (Lightbown and Spader, 1999).

5. Natural Order Hypothesis
• Language is acquired in a predictable
order by all learners. This order does not
depend on the apparent simplicity or
complexity of the grammatical features
involved. The natural order of acquisition
cannot be influenced by direct teaching
of features that the learner is not yet
ready to acquire.

6. Natural Order Hypothesis
• It is claimed that the natural order of
acquisition is very similar for a native-English
child learning its own language and for an
adult learning English as a foreign language.
• For example, the ’-ing’ form (present
continuous) will be acquired early on and
almost certainly before the ’-s’ inflection in
the third person present simple (she likes, he
eats, etc.)

7. Natural Order Hypothesis
• As Krashen points out, much of the
frustration experienced by teachers
and their students in grammar
lessons results from the attempt to
inculcate a grammatical form which
the learner is not yet ready to
acquire.

8. Monitor Hypothesis
• We are able to use what we have
learned (in Krashen's sense) about the
rules of a language in monitoring (or self-
correcting) our language output.
• Conscious editor or monitor works.
• Clearly, this is possible in the correction
of written work. It is much more difficult
when engaging in regular talk.

9. Monitor Hypothesis
• Krashen states that it is often difficult to use the
monitor correctly since the rules of a language can be
extremely complex.
• Two examples from English are the rules about the
articles (a/the) and the future "tense".
• Even assuming the learner has a good knowledge of
the rule in question, it is difficult to focus on grammar
while simultaneously attempting to convey meaning
(and possibly feeling).
• Most normal conversation simply does not provide
enough time to do so.

10. Monitor Hypothesis
• There are variations in use of the monitor that
affect the language that learners produce.
• Acquired language skills can lead to improved
fluency but overuse of the monitor can lead to
a reduction in fluency (Krashen, 1988).
• Moreover, Krashen (1988) believes that there
is individual variation among language
learners with regard to ‘monitor’ use.

11. Monitor Hypothesis
• He claims that the learners who use the
‘monitor’ all the time are ‘over-users’,
often producing stilted language,
whereas ‘under-users’ will often speak
quickly but with a lot of errors.
• Learners who use the monitor
appropriately are considered ‘optimal-
users’.

12. Monitor Hypothesis
• These find a good balance between
speed and accuracy, continuing to refer
to want they have learnt but
acknowledging the importance of
communication.
• He emphasizes that lack of self-
confidence is the major cause for the
over-use of the ‘monitor’.

13. Input Hypothesis
• We acquire language in one way only: when
we are exposed to input (written or spoken
language) that is comprehensible to us.
• Comprehensible input is the necessary but
also sufficient condition for language
acquisition to take place. It requires no effort
on the part of the learner.

14. Input Hypothesis
• Krashen now refers to this as the Comprehension
Hypothesis.
• It states that learners acquire language when
they are exposed to input at i+1, where i is the
current state or stage of language proficiency.
• Learners use their existing acquired linguistic
competence together with their general world
knowledge to make sense of the messages they
receive in language just beyond where they
currently are (the +1).

15. Input Hypothesis
• Given comprehensible input at i+1, acquisition
will take place effortlessly and involuntarily.
• This theory has clear implications for language
teachers; namely, that their language
instruction should be full of rich input (both
spoken and written language) that is roughly
tuned at the appropriate level for the learners
in the class.

16. Affective Filter Hypothesis
• Comprehensible input will not result in
language acquisition if that input is
filtered out before it can reach the
brain's language processing faculties. The
filtering may occur because of anxiety,
poor self-esteem or low motivation.

17. Affective Filter Hypothesis
• Learners with a low affective filter will
not only be efficient language acquirers
of the comprehensible input they
receive. They are also more likely to
interact with others, unembarrassed by
making mistakes for example, and thus
increase the amount of that input.

18. Affective Filter Hypothesis
• He claims that learners who are highly
motivated, self-confident and less anxious are
better equipped for success in SLA.
• Low motivation, low self-esteem, and high
anxiety contribute to raise the affective filter
which prevents comprehensible input from
being used for acquisition.

19. Affective Filter Hypothesis
• In other words, if the filter is high, the
input will not pass through and
subsequently there will be no
acquisition.
• On the other hand, if the filter is low and
the input is understood, the input will
take place and acquisition will have
taken place.

20. Affective Filter Hypothesis
• Gass and Selinker (1994) criticize the Filter
Hypothesis because it does not explain how it
works? Or how the input filter works?
• However, others see that it as something that
can be seen and applied in the classroom and
that it can explain why some students learn
and produce better language than others
(Lightbown and Spader, 1999).

21. • Thank you for listening 
• Haifa Alzmami.