Word: 四十五 (sì shíwǔ)

全班的总数是四十五人。

Quánbān de zǒngshù shì sì shíwǔ rén.

The total number in the whole class is forty-five.

六点四十五了。

Liù diǎn sì shíwǔ le.

It's a quarter to seven.

每个课时是四十五分钟。

Měige kèshí shì sì shíwǔ fēnzhōng.

Each period is forty-five minutes long.