うっかり

Ukkari himitsu o hanashite shimaimashita.

I carelessly let the secret slip.

Shukudai o ukkari wasurete shimaimashita.

I accidentally forgot my homework.

Ukkari shite ite, densha o norisugoshite shimaimashita.

I wasn't paying attention and missed my stop on the train.

Kasa o densha no naka ni ukkari okiwasurete shimaimashita.

I carelessly left my umbrella behind on the train.

Ukkari sumaho o otoshite, gamen ga warete shimaimashita.

I accidentally dropped my smartphone and cracked the screen.

Daiji na kaigi no jikan o ukkari machigaete shimaimashita.

I carelessly mistook the time of the important meeting.