Assimilation is a process in pronunciation where nearby sounds influence each other. It can happen in two directions: REGRESSIVE ASSIMILATION is when the next sound influences the first one - for example the /n/ in INCREASE becomes /ŋ/, matching the position of the following /k/. PROGRESSIVE ASSIMILATION is when the first sound influences the next one - in "PASS THE", the /s/ changes the position of /ð/ to match its own so the TH can be pronounced /z/ in connected speech. Assimilation is widespr