I don't know what they'll want when they arrive—we'll have to play it by ear.

我不知道他们到达时需要什么—我们只有见机行事了。

《牛津词典》

When they arrive, I'll let you know at once.

当他们到达时，我会马上通知你。

youdao

Both Jean and Bill are tired when they arrive home at 6 pm.

当下午6点回到家时，琼和比尔都很累。

youdao

When crime scene investigators arrive at the place of a crime, they first try to make sure the area is secure.

VOA: special.2010.05.05

"There is a sense that when the political leaders arrive in the next few days, that they will be able to overcome some of the stumbling blocks, because I believe the leaders will be able to really grab this issue by the scruff of the neck and get down to the substance and bridge the remaining gaps,".

VOA: standard.2009.12.17

But when they arrive, they are going to find some very up-to-date competitors, such as Orix.

FORBES: The sun also rises

Jindal suspended registration at the terminal and instructed people to register when they arrive at shelters.

CNN: Mandatory evacuations to begin Sunday morning in New Orleans

Her kids' friends are expected to deposit their devices there when they arrive for a party.

WSJ: Social Media Etiquette at Parties: When Facebook, Twitter and Instagram Are the Guests