Dialogue is a huge part of any novel. It helps define a character and allows us into their thoughts. One part of language is often missed out. The body language.
We all know that only a tiny amount of communication is about the actual words used. The intonation, the setting, it can change the entire meaning of a phrase. For example, a woman looking at a picture downloaded from a site not to be seen by children, might say, “that’s sick”. She really means, “I find this the behaviour of someone who does not have what I consider to be good morals.” Her teenage son might (if it is not in front of his mother), use the word sick to mean fascinating, exciting. Same setting, same words, totally different meaning. And the dad, who agrees it’s sick but winks at his son behind his wife’s back – well, that’s another meaning all together.
So how do we show the different intonation and actions that are vital for understanding? Well, a distinctive body movement can show someone is lying. “She dropped her eyes before replying.” Culturally though, these signals can be vastly different. A Muslim woman speaking to a man not in her family must drop her eyes to stay modest. Meeting the eyes of someone you are talking to for some Indigenous Australians is the height of rudeness. There are dozens of examples of one group thinking the exact opposite of the other. I suppose the main thing is to be true to your voice and add in the intonation and body language to help clarify the tone.