A passenger airplane flying high above soft clouds in a bright sky.

Big question

为什么飞机能飞在天上？

Wèishénme fēijī néng fēi zài tiānshàng?

Why do airplanes stay up?

飞机能飞在天上，是因为它的翅膀穿过空气的时候，会让飞机被空气托起来。

Fēijī néng fēi zài tiānshàng, shì yīnwèi tā de chìbǎng chuānguò kōngqì de shíhou, huì ràng fēijī bèi kōngqì tuō qǐlái.

飞机会很快很快地往前飞。空气流过翅膀的时候，翅膀会帮助把飞机往上托，而引擎会一直推着它往前走。往上托的力量和往前飞的力量一起帮忙，飞机就可以在天空中飞行了。

Fēijī huì hěn kuài hěn kuài de wǎng qián fēi. Kōngqì liúguò chìbǎng de shíhou, chìbǎng huì bāngzhù bǎ fēijī wǎng shàng tuō, ér yǐnqíng huì yìzhí tuīzhe tā wǎng qián zǒu. Wǎng shàng tuō de lìliàng hé wǎng qián fēi de lìliàng yìqǐ bāngmáng, fēijī jiù kěyǐ zài tiānkōng zhōng fēixíng le.

如果你从飞机窗户往外看，你觉得自己会先看到云，还是地上小小的东西呢？

Rúguǒ nǐ cóng fēijī chuānghu wǎng wài kàn, nǐ juéde zìjǐ huì xiān kàndào yún, háishì dìshang xiǎoxiǎo de dōngxi ne?

Airplanes stay up because their wings move through the air in a way that helps lift them.

An airplane zooms forward very fast. As air moves around its wings, the wings help push the airplane up while the engines keep it moving ahead. With lift pushing up and the engines carrying it forward, the airplane can travel across the sky.

If you looked out an airplane window, what clouds or tiny things on the ground do you think you would notice first?