到达机场后，我们需要登记。

Dàodá jīchǎng hòu, wǒmen xūyào dēngjì.

After arriving at the airport, we need to register.

婚礼前，新人需要登记结婚。

Hūnlǐ qián, xīnrén xūyào dēngjì jiéhūn.

Before the wedding, the couple needs to register for marriage.

护照丢失后，我去登记了。

Hùzhào diūshī hòu, wǒ qù dēngjìle.

After losing my passport, I went to register.