Passengers line up at the gate to board the plane.

乘客们在登机口排队准备登机。

His passport is lost, so he can't board the plane.

他的通行证丢失了，所以他不能登机。

The airport has ramps to help passengers board the plane.

机场有斜坡帮助乘客登机。

He lost his air ticket, so he can't board the plane.

他的飞机票丢了，所以他不能登机。

He forgot to bring his ID card, so he couldn't board the plane.

他忘记带身份证，所以无法登机。

There were 230 people on board the plane.

飞机上有230人。

What time do I re board the plane?

我什么时候再上飞机？

When is the latest time for me to board the plane?

我可以最迟什么时候登机?

The hijackers kept the pilot on board the plane as a hostage.

劫机者把飞机驾驶员扣留在飞机上作为人质.

The hijackers kept the pilot on board the plane as (a) hostage.

劫机者把飞机驾驶员扣留在飞机上作为人质。