Liaison is one of the most common ways that English pronunciation is affected. Sometimes called assimilation or sandhi, depending on the case, liaison generally refers to two adjoining sounds blending together. It helps to think of letters and sounds as being "sticky." They attach to the sounds around them and influence them. In English, this often happens between words so that entire phrases or sentences are pronounced as one chunk.
Let's look at some examples of when and how this occurs.
When a consonant precedes a vowel: The two sounds link together and are pronounced without a pause in between the words. Unvoiced consonants sometimes become voiced ones (t sounds like d, s sounds like z).
Example: His name is Eric. The m in name and the i in is will join together and be pronounced like "namis." The s in is and the E in Eric will liaison, making the s sound more like a z. All together it sounds like "His namizEric."
When a consonant precedes another consonant make in the same area of the mouth: The two sounds join together and are pronounced without a pause.
Example: get the dog, kick her The t of get and the th of the will join together. This makes the t sound a little softer. K and h are both made on the back roof of the mouth, so they join together to sound like "kicker."
When a vowel precedes another vowel: A glide, or a soft y or w sound, is added between the two and it is all pronounced together. Whether a y or w sound is used will depend on the lip position. When the vowels require rounded lips, it will naturally become a w sound. Otherwise, it should be y.
Example: go out, I am The two o's of go out get separated by a w glide so that it sounds like "gowout." Likewise, I am becomes "Iyam."
When T, D or Z sound precedes a Y: The sounds blend together, sounding like ch, j and zh respectively. Rem
Example: Nice to meet you. Did you know that? How's your mother? Here meet you becomes "meechoo," Did you becomes "dijou," and How's your becomes "howzher" since the s makes a z sound.