1. 4.1.4 The four groups’ average performances of / ʃ /, /t ʃ / and /d ʒ / 3176Hz English native speakers place their tips of tongues in a further back location than the other three groups. 3706Hz 4002Hz 3590Hz The LPC average of / ʃ /,/t ʃ / and /d ʒ / at the coda 3619 Hz Group 3 Group 2 Group 1 Group 4

2. 4.1.5The effects of an additional four years of English learning experience 4.1.5.1 Group 2 vs. Group 3

3. 4.1.5The effects of an additional four years of English learning experience ＊ As seen in Table, Group Three does not produce the six fricatives and affricates significantly differently from Group Two. ＊ This is because the p values of these sounds are all above.05. ＊ This result supports the first hypothesis, that an additional four years of English learning experience is not helpful in improving pronunciation of the L2 similar phonemes. 4.1.5.1 Group 2 vs. Group 3

4. 4.1.5The effects of an additional four years of English learning experience ＊ As seen in Table, Group Four does not produce the six fricatives and affricates significantly differently from Group Three. ＊ This is because the p values of these sounds are all above.05. ＊ This result supports the first hypothesis, that an additional four years of English learning experience is not helpful in improving pronunciation. 4.1.5.1 Group 3 vs. Group 4

5. 4.1.6 The effects of an additional eight years of English learning experience(Group 2 vs. Group 4 )

6. 4.1.6The effects of an additional eight years of English learning experience ＊ An additional eight years of English learning experience are not effective in improving pronunciation because none of the p values of / ʒ /,/θ/,/ð/,/t ʃ /, /d ʒ /, and / ʃ / are below.05. － Therefore, the second hypothesis is not supported. － This result provides support for the Speech Learning Model (SLM), which is based on the concept that even though one an L2 learner is experienced, they still cannot produce phonemes in ways that are exactly the same as an L2 native speaker can. Group 2 vs. Group 4

7. Chapter Four: Results and Analysis

8. 4.2 / ʒ /,/θ/,/ð/,/t ʃ /, /d ʒ /, and / ʃ / as onsets before / ɚ / ＊ The greater number of the peak value it is, the more to the front the tip of the tongue is. ＊ Moreover, the F2 of the CV transient is compared.

9. 4.2 / ʒ /,/θ/,/ð/,/t ʃ /, /d ʒ /, and / ʃ / as onsets before / ɚ / ＊ The order of the tip of the tongue from front to rear of Group One is /ð/(4822)> {/t ʃ /(3621),/ ʃ /(3334), / ʒ /(3275), /d ʒ /(3013)}. ＊ The order of the tip of the tongue from front to rear of Group Two is /ð/(4741)> / ʒ / (4608)> /d ʒ / (4275)> / ʃ /(4124)> /t ʃ / (3579). － /d ʒ /, and / ʒ / with significant difference from Group One. The p value of /d ʒ / is.025, of / ʒ / is.000. － Taiwanese students tend to replace / ʒ / with /d ʒ /, and some English native speakers do the same. 4.2.1 Group 2 vs. Group 1(English Native Speaker)

10. 4.2 / ʒ /,/θ/,/ð/,/t ʃ /, /d ʒ /, and / ʃ / as onsets before / ɚ / ＊ The order of the tip of the tongue from front to rear of Group One is /ð/(4822)> {/t ʃ /(3621),/ ʃ /(3334), / ʒ /(3275), /d ʒ /(3013)}. ＊ The order of the tip of the tongue from front to rear of Group Three is /ð/(5294)> / ʃ /(4362)> {/ ʒ /(3832), /t ʃ / (3756), /d ʒ / (3697)} － /t ʃ /,/d ʒ / and / ʒ / with significant differences from native speakers. The p value of / ʒ / is.007, of /d ʒ / is.004, and of / ʃ / is.008. 4.2.2 Group 3 vs. Group 1(English Native Speaker)

11. 4.2 / ʒ /,/θ/,/ð/,/t ʃ /, /d ʒ /, and / ʃ / as onsets before / ɚ / ＊ The order of the tip of the tongue from front to rear of Group One is /ð/(4822)> {/t ʃ /(3621),/ ʃ /(3334), / ʒ /(3275), /d ʒ /(3013)}. ＊ The order of the tip of the tongue from front to rear of Group Four is /ð/(4946)>/ ʃ /(4014)>{/ ʒ /(3306),/t ʃ /(3172),/d ʒ /(2940)}. － / ʃ / with a significant difference, with a p value of.026. 4.2.3 Group 4vs. Group 1(English Native Speaker)

12. 4.2.4 The four groups’ average performances of / ʃ /, /t ʃ / and /d ʒ / 4.2.4.1 The comparison of the four groups’ LPC average performances of /t ʃ /, /d ʒ /, and / ʃ / before / ɚ / 3323Hz English native speakers place their tips of tongues in a further back location than the other three groups. 3993Hz 3938Hz 3375Hz The LPC average of / ʃ /,/t ʃ / and /d ʒ / before / ɚ / 3657 Hz Group 3 Group 2 Group 1 Group 4

13. 4.2.4 The four groups’ average performances of / ʃ /, /t ʃ / and /d ʒ / ＊ All four groups place the tips of their tongues in a more front location when producing /t ʃ /, /d ʒ /, and / ʃ / than when pronouncing / ɚ / because the overall trend is from high frequency to low frequency. ＊ Group 1 CV transient from palatals to schwa does not show any significant changes, and thus when this group pronounces /t ʃ /, /d ʒ /, and / ʃ / with / ɚ /, they place their tongues in similar locations. ＊ Group Four’s performances of the palatals before / ɚ / are closer to those of Group One. 4.2.4.2 The four groups’ second formants in the CV transient

14. 4.2.5The effects of an additional four years of English learning experience ＊ As seen in Table, Group Three does not perform significantly differently from Group Two. ＊ This is because the p values of these sounds are all above.05. ＊ This result supports the first hypothesis, that an additional four years of English learning experience is not helpful in improving pronunciation of the L2 similar phonemes.. 4.2.5.1 Group 2 vs. Group 3

15. 4.2.5 The effects of an additional four years of English learning experience ＊ As seen in Table, Group Four does not produce the fricatives and affricates significantly differently from Group Three. ＊ This result supports the first hypothesis, the additional four years of English learning experience at school is not one of the factors that improve the pronunciation of L2 similar phonemes. 4.2.5.1 Group 3 vs. Group 4

16. Thank You!