1put__ cut__ hit__ read__ let__beat__ hurt__ cost和动词原形同型
2kept,slept,swept去掉e加t
3taught,caught,加aught
4brought,bought,thought,加ought
5began,drank,rang,sang,swam,sat,变i为a
6lent,sent,spent,built,变d为t
7sold,told,变ell为old
8,said,paid,变y为id
9met,fed,去掉一个e
10grew,knew.threw,flew.变o为e