寝(ね)過(す)ごすto oversleep

寝過(ねす)ごして学校(がっこう)に遅刻(ちこく)しました。

I overslept and was late for school.

会議(かいぎ)に遅(おそ)れたのは寝過(ねす)ごしたせいです。

The reason I was late for the meeting was because I overslept.

寝過(ねす)ごして授業(じゅぎょう)に遅(おそ)れたら、先生(せんせい)に怒(おこ)られた。

I overslept and was late for class, and the teacher got angry.

絶対(ぜったい)に寝過(ねす)ごして飛行機(ひこうき)に乗(の)り遅(おそ)れたりなど出来(でき)ない。

I absolutely cannot oversleep and miss my flight and such.

授業(じゅぎょう)に何(なに)度(たび)も寝過(ねす)ごして遅刻(ちこく)したのなら、進級(しんきゅう)できないのも当然(とうぜん)だ。

If you overslept and were repeatedly late for class, it's only natural that you can't advance to the next grade.