Reduction

There are certain words in English which have two forms of pronunciation: strong, or full, form and weak, or reduced, form.

These words include form-words, modal verbs and pronouns: personal, possessive, reflexive, relative, etc.

The following functional words are never used in their strong form in an unstressed position in an utterance:

Word	Strong form	Weak forms
a	[eI]	[q]
an	[xn]	[qn]
and	[xnd]	[qn], [n]
but	[bAt]	[bqt]
than	[Dxn]	[Dqn]
that (conjunction)	[Dxt]	[Dqt]
the	[DJ]	[Dq] – before a consonant [Di], [DI] – before a vowel
them	[Dem]	[Dqm]
there (pronoun)	[DFq]	[Dq] – before a consonant [Dqr] – before a vowel
us	[As]	[qs]
There is also a group of words that are reduced when unstressed at the beginning or in the middle of an utterance, but remain strong in the final position:
am	[xm]	[qm], [m]
are	[R][Rr]	[q] – before a consonant [qr] – before a vowel
is	[Iz]	[z], [s]
was	[wPz]	[wqz]
were	[wE:]	[wq] – before a consonant [wqr] – before a vowel
will	[wIl]	[l]
would	[wVd]	[d]
shall	[Sxl]	[Sql], [Sl]
should	[SVd]	[Sqd], [Sd]
have	[hxv]	[hqv], [qv], [v]
has	[hxz]	[hqz], [qz], [z]
had	[hxd]	[hqd], [qd], [d]
do	[dH]	[du], [dV], [d]
does	[dAz]	[dqz]
must	[mAst]	[mqst], [mqs]
can	[kxn]	[kqn], [kn]
could	[kVd]	[kqd]
some (determiner)	[sAm]	[sqm]
as	[xz]	[qz]
at	[xt]	[qt]
from	[frPm]	[frqm]
for	[fL]	[fq] – before a consonant [fqr] – before a vowel
of	[Pv]	[qv]
to	[tH]	[tq] – before a consonant [tu] – before a vowel or finally

Prepositions have their strong forms though they might remain unstressed:

1. at the very end of an intonation groups or phrase;

E. g.: Where have you come from?

What are you looking at?

Who are you looking for

Where are you going to?

2. at the end of an intonation group or phrase when they are followed by the unstressed pronouns;

E. g.: He’ll make his fortune at it.

There’s something for you.

3. polysyllabic prepositions followed by a pronoun at the end of a phrase are stressed as a rule.

E. g.: I’ve never heard about her.

Auxiliary and modal verbs have their strong forms:

1. at the end of an intonation group or a phrase;

E. g.: Who is on duty today? - I am.

We didn’t know where he was

2. at the beginning of general and alternative questions in careful colloquial style, while in rapid colloquial style are unstressed and reduced;

E. g.: Could you tell me his name?

3. in contracted negative forms.

Some form-words are always used in their strong form. They are never reduced:

Words always strong in an unstressed position

To be (is, are), to do (do, does), to have (has, have, had) when they function as main verbs;

When, then (adverbs);

On, off, in;

Will (modal verb);

That (demonstrative pronoun);

Some (indefinite pronoun);

What, where, how, which, with.

E. g.: For some (certain) reason they didn’t arrive on time. On the ground floor there are three rooms. Then go and help him. That dress is more beautiful than this one.

There are three degrees of the reduction of strong forms.

1. the reduction of the length of a vowel without changing its quality (quantitative reduction)

E. g.: you [jH] → [ju], me [mJ] → [mi].

2. The reduction of the quality of a vowel (qualitative reduction)

E. g.: her [hE:] → [hq], for [fL] → [fq].

3. The omission of a vowel or a consonant sound (zero reduction)

E. g.: I am → I’m [aIm]; I have → I’ve [aIv]; does not → doesn’t [dAznt].