Conjugation of toughen [v.]
-toughen
Itoughen
youtoughen
hetoughens
wetoughen
youtoughen
theytoughen
Itoughened
youtoughened
hetoughened
wetoughened
youtoughened
theytoughened
Iwilltoughen
youwilltoughen
hewilltoughen
wewilltoughen
youwilltoughen
theywilltoughen
Ihavetoughened
youhavetoughened
hehastoughened
wehavetoughened
youhavetoughened
theyhavetoughened
-toughening
-toughened