Some words are harder to pronounce than others. Certain traits from a person's native language typically bleed over into the new language, a phenomenon known as language transfer. Language transfer can be positive or negative — meaning, it can help or hinder you when trying to pronounce words in the language you're unfamiliar with [source: Conti].
"For example, English uses two sounds which we can refer to the 'th' sounds (a voiceless sound as in "think" and a voice sound as in "the"). Many languages do not include this sound in their inventory — and in fact, don't make any sounds where the tongue is between the teeth," emails accent and dialect coach Melanie Fox.
This negative transfer might cause a person new to the English language to substitute a similar sound, in place of the unfamiliar "th." "For example, German native speakers may substitute an 's' or 'z' for the 'ths,' while a speaker of Italian or South/Latin American Spanish may use a 't' or a 'd.' This could cause 'think' to sound like 'sink,' 'tink,' or even 'fink' depending on the native language of the speaker," Fox says.
But if there is a level of similarity between the first and second languages, then transfer can be helpful. For example, people who speak Italian have less trouble pronouncing the "p" sound in Spanish because the two languages say it the same way, which results in positive transfer [source: Conti].
Everything about how a person talks, from tongue placement to lip curling to nose airflow, can affect pronunciation. Blocking airflow with your mouth or vibrating your vocal cords when you shouldn't can also cause you to mispronounce words. These seemingly small variations have a major effect on the outcome of an accent unless the speaker successfully adapts, typically through in-depth practice and a variety of oral pronunciation activities [source: Lingholic].