helodium

例句：

1. 1. Helium is a noble gas that is used in rockets and spacecraft.
   氦是一种稀有气体，用于火箭和宇宙飞船。
2. 2.The helium-filled balloon floated high above the clouds.
   充满氦气的气球飘浮在云层之上。
3. 3. Helium is heavier than air, so it can be used to lift objects.
   氦比空气重，因此可以用来提升物体。