Rhythm

Rhythm in English comes from two different areas:

1-Word stress

In order to understand word stress in English, you need to know what a syllable is. A syllable can only be one of two things:

1 vowel OR
1 vowel + 1 consonant

To have a syllable then, you must have at least 1 vowel. The number of consonants is not important.
For example: sun.

[s] is consonant[u] is a vowel[n] is a consonant

That means the word [sun] has 2 consonants and 1 vowel. So how many syllables does it mean the word [sun] has? The answer is: 1 syllable. The reason is that it only has 1 vowel.
One more example: how about the word [Macdonald]?

[m]is a consonant
[a]is a vowel
[c]is a consonant
[d]is a consonant
[o]is a vowel
[n]is a consonant
[a]is a vowel
[l]is a consonant
[d]is a consonant

How many vowels does the word [Macdonald] have then? 3 vowels.

Macdonald
123

So when you pronounce the word [Macdonald], you should only pronounce 3 syllables, not 4 and not 5, otherwise, listeners will be very confused and will probably ask you to repeat, which can be embarrassing.

Most 2 or 3-syllable words also have 1 stress but… some 4 or more syllable words could have 2 stresses, 1 primary stress and 1 secondary stress.

Let’s see some examples of word stress:

1-syllable wordino
2-syllable wordinstantOo
3-syllable wordinstantlyOoo
4-syllable wordinstantiateoOoo
5-syllable wordinstantaneousooOoo
6-syllable wordinstantaneouslyooOooo

2-Sentence Stress

In English, sentence stress is the key to creating the rhythm of the language. Rhythm, among a few other things, is what native speakers depend on to understand the message(s) of the speaker. In English, we usually stress

1-Nouns2-Verbs3-Adverbs4-Adjectives
Example 1
Myfriend'sinvitedmetohisparty
PronounNounVerbPronounPrepositionPronounNoun
 o O o O o o o o O o

Do not be confused between word stress and sentence stress. In word stress, we look at the syllable we stress in a word, but in sentence stress, we look at the word we stress in a sentence.
Now let’s make the sentence longer by adding an adjective and adverb.

Example 2
Mynewfriend'sinvitedmetohispartyeagerly
PROADJNOUNVERBPRONPREPPRONNOUNADV
 o O o o O o o o o O o Ooo

It depends on the purpose of the message we're trying to communicate, but in general, we stress the nouns, verbs, adjectives and adverbs (content words) in the sentence as they are the ones that essentially carry the full weight of the message.
Notice that [my] [the] [me] [to] and [his] (referred to as "function" words) were not stressed in example 2 because they bore no impact on the meaning of the sentence. That is generally the case. However, there are many situations when we do stress the "function" words as follows:
1-My new friend's invited ME to his party (not YOU)
2-My friend's invited me to HIS party (not YOUR party)

Word Stress Rule 1

Only 1 syllable can be stressed in a word.

In long words, there can be 1 primary stress and 1 secondary stress. It is important to remember that 1 vowel forms 1 syllable; the numbers of consonants do not count.
For example:
"sing" is 1 syllable; 1 vowel and 2 consonants (s-i-ng)
"sting" is 1 syllable; 1 vowel and 3 consonants (s-t-i-ng)
"string" is 1 syllable; 1 vowel and 4 consonants (s-t-r-i-ng)
"hamstring" is now 2 syllables; 2 vowels and 6 consonants
"hamstring" can only have 1 stressed syllabe (HAMstring)

Word Stress Rule 2

In 2-syllable nouns, the first syllable is normally stressed.

For example:

Oo
TAble
CARpet
COUNtry
HUman
DOCtor

Word Stress Rule 4

In 2-syllable verbs, the second syllable is normally stressed, but there are many exceptions to the rule.

For example:

oO Exceptions
conVENE TRAvel
purSUE ANswer
conCEDE BOrrow
deTER CArry
preVENT STUdy

Word Stress Rule 3

In 2-syllable adjectives, the first syllable is normally stressed.

For example:

Oo
HAppy
UGly
YEllow
FANcy
LOVEly

Word Stress Rule 5

In 3-syllable verbs ending with either -ly or -er (the -er is not really a rule but rather a common pattern, the first syllable is normally stressed.

For example:

-Ooo-Ooo
UsuallyGARdener
BEAUtifullyMAnager
RECKlesslyPUBlisher
INStantlyCARpenter
NORmallyCHAracter

Word Stress Rule 6

In words with suffixes -sion, -tion, -cian, -ious, -ic, -ient, -ial, -able, -ia, -ish, stress falls on the syllable preceding them, -Oo if the suffix consists of 1 syllable like -ic, and -Ooo if it consists of 2 syllables like -able. Some suffixes can either be pronounced as 1 syllable or 2 syllables depending on what precedes them like -ian.

For example:

-sion -tion -ian -ious -ic
deCIsion sepeRAtion techNIcian deLIcious fanTAStic
oCCAsion opeRAtion elecTRIcian superSTItious bomBAStic
coRROsion compenSAtion beauTIcian reLIgious eLAStic
coHEsion fruItion coMEDian noTOrious eRRAtic
aBRAsion coaLItion ciVILian feROcious pragMAtic

-ient -ial -able -ia -ish
inGREdient fiNANcial CApable amNEsia SELfish
oBEdient oFFIcial DUrable MEdia FLOUrish
suFFIcient experiENtial DRINkable acaDEMia esTABlish
imPAtient eSSENtial DOable leuKEMia rePUBlish
LENient FAcial REAdable aNEMia repLEnish

Word Stress Rule 7

In words with suffixes -cy, -ty, -phy, -gy, -al, stress falls on the 2nd syllable preceding them (-O0cy, -Ooty, -Oophy, -Oogy, -Ooal).

For example:

-cy -ty -phy -gy -al
INfancy aBIlity phoTOgraphy biOlogy alphaBEtical
deMOCracy norMAlity caLLIGraphy Allergy aboROginal
FAllacy abSURdity aPOStrophy aPOlogy ADmiral
FREquency adVERsity caTAStrophy LEthargy CULtural
auTOCracy DIGnity geOgraphy phoNOlogy indisPENsable

Word Stress Rule 8

In many (not all) words with suffixes -ade, -ee, -eer, -ese, -que, -oon, the suffix itself is stressed.

For example:

-ade-ee-eer-ese-que-oon
cruSADEguaranTEEpuppeTEERJapaNESEphySIQUEbaLOON
tiRADEaddreSSEEauctioNEERVietnaMESEmysTIQUEcarTOON
briGADEappoinTEEmarkeTEERNepaLESEuNIQUEbaFOON
inVADEagREEpioNEERChiNESEtechNIQUEraCOON
perSUADEconsiGNEEvolunTEERMalTESEobLIQUEtyPHOON

Word Stress Rule 9

When a noun comprises two words, the first syllable is stressed.

For example:

Oo
BLACK-board
SUN-rise
SWIM-wear
BED-room
BASket-ball

Word Stress Rule 10

In reflexive pronouns, the second syllable is always stressed.

For example:

oO
mySELF
themSELVES
ourSELVES
yourSELF
himSELF