Listening focuses on understanding spoken language. It means that sounds, words, and sentences are joined to have a connected speech. Connected speech is when people communicate in a certain language, every word has some effects on each other.
Catenation or linking: It happens when the end of a word blends into another. For example, the word 'this' links with 'afternoon' and sound: thisafternoon
Intrusion: An additional sound is inserted between others. For example, when someone pronounces 'He asked' and sounds like this: heyasked.
Elision: It is when a sound disappears by other stronger or similar. For example, in 'dad take' people usually pronounce 'datake'
Assimilation: Tow sounds blend together and produce a single one. For example, the words 'Did you' sound like this: diʤu.
Geminates: When one word ends with the same letter as the beginning of the other word. Those words are pronounced together. For instance, social life sounds socialife.
Remember that it's necessary to have clear these points about connected speech. It will facilitate the listening understanding.
Wallace, G. (2020). 5 Connected Speech Secrets for Fast, Native English Pronunciation. https://www.gonaturalenglish.com/connected-speech-fast-native-english-pronunciation/