詞綴：sub-,sup-,suc-,sus-

意思：下，向下 subway；從下往上 submit；亞于，次于 suburban；后，后面 subsequent；

詞綴：-ity -lity -ilty:名詞后綴

-itate：使…（動詞）

de-：向下

com- col- con- co- cor-：等于with，共同一起；加強語氣；

anc-：以前；老/高

詞匯

success，succeed，succeeding，successful，successfully，successor，succession，a succession of，successive

necessary，necessitate

degrade，degradation

upgrade，upgradation

gradual，gradually

congress，congressional，congressman

ancestor，ancestry，ancestral

concede，concession