During conversation, people speak with a relaxed attitude toward the formal sounds that each word contains. If someone were to pronounce each sound as they should be spoken, the words would sound broken, robotic and awkward. Indeed, even during formal speeches, words have a tendency to run together. Words are spoken with more fluidity, allowing beginning and end sounds to transition smoothly into one another using a variety of methods. This phenomenon is called connected speech.
When speaking, sounds are created. They often flow into each other or completely disappear. What determines this is which sounds follow another: consonant followed by consonant, consonant followed by vowel or vowel followed by vowel. When a word ends with a consonant and is followed by another consonant, the sounds might either assimilate or elide during connected speech.
Assimilation occurs when the ending of the first word merges with the beginning sound of the other. For instance, in the phrase “Is Sally?” the /z/ sound in “is” softens to meet the soft /s/ of “Sally.” Anticipatory assimilation happens when the tongue naturally places itself in a position closest to the next sound. For instance, “that kite” versus “hot meringue.” Assimilation is not typically a necessary technique in connected speech, but it still tends to happen naturally during conversation.
"Elision" is the term for sounds or even an entire syllable completely disappearing. Though this happens mainly with consonant-and-consonant words, elision also occurs with small, unstressed words and vowels. The /t/ and /d/ sounds are usually the most affected, as in “next week” or “mold the clay.”
Consonant-to-vowel or vowel-to-consonant provides an easier link because these sounds naturally transition when spoken. These will either link or R-link. With linking, the ending sound will simply fold into the next sound. R-linking refers specifically to British English, where the ending /r/ sound is not usually pronounced. Only when it follows a vowel is the /r/ pronounced in connected speech.
A vowel followed by vowel is another combination that is unnatural for the tongue to pronounce. To make the connection more fluid, an extra sound is thus created. This is done in two main ways: using the intrusive /r/ or adding /j/ or /w/. One example is the /w/ sound added to the phrase “to it.”