空kōng · kòng
empty, a vacuum. 8 strokes, radical 穴, first met in HSK 2.
What 空 is made of
穴 (xué, cave) and 工 (gōng, labor).
穴 carries the meaning — cave — and 工 carries the sound.
How to write 空
Strokes 1–5 write 穴, then strokes 6–8 write 工.
Free, with no account: the app draws each stroke, then you write it and it says which stroke went wrong.
Print a 米字格 practice sheet for 空
Words that use 空
| 空 | empty, a vacuum 里面什么都没有的状态 密闭容器内被抽成了真空环境。Inside the sealed container, a vacuum environment was created. Lesson 219, 物理求索与工业实验 · 科学探索与实验求索 · Scientific Exploration, Laboratory Experiments & Physical Inquiry |
| 空气 | air 包围在地球周围，我们呼吸用的气体 雨后山间空气格外清新。After the rain, the air in the mountains feels especially fresh. Lesson 45, 快乐课堂 · 研精竭虑与博闻多能 · Rigorous Inquiry & Versatile Learning |
| 天空 | the sky 头顶上又高又蓝的地方 早晨的天空一片蔚蓝，没有一朵云。This morning the sky was a clear, deep blue with not a cloud. Lesson 116, 天气与阳光 · 壮丽自然与旅行见闻 · Magnificent Nature & Travel Exploration |
| 空调 | air conditioning 调节室内温度的电器 夏天太热，办公室都装了空调。Summers get so hot that every office has air conditioning installed. Lesson 188, 机械动力与工业实力 · 工艺制造与机械生产 · Industrial Manufacturing, Engineering & Quality Control |
| 空儿 | free time 忙碌之间挤出来的一小段闲暇时间 忙完了农活，乡亲们才有了空儿歇息。Only once the farm work was done did the villagers find free time to rest. Lesson 206, 田园闲暇与岁月悠长 · 乡村农业与田园风光 · Rural Agriculture, Countryside Life & Harvest Seasons |
| 航空 | the commercial aviation industry 利用飞机在空中运输的行业 民用航空飞速发展，十分便捷。Civil aviation has developed rapidly and become very convenient. Lesson 289, 蓝天翼展与桑梓归怀 · 海洋生态与四海远航 · Oceanic Ecology, Aviation & Winter Horizons |
| 空间 | space 可以活动或摆放东西的地方 热气球缓缓降落在开阔空间。The hot air balloon slowly landed in the open space. Lesson 305, 广阔天地与谦逊笃行 · 镜里乾坤与天地广厦 · Reflections, Pastoral Havens & Broad Horizons |
| 填空 | fill-in-the-blank 在空白处补上正确答案的练习题 员工要认真完成填空练习。Staff must carefully finish a fill-in-the-blank test. Lesson 344, 维权明晰与合意套餐 · 资政明辨与赤子勇毅 · Insightful Governance & Innocent Courage |
| 空中 | in the air, aloft 指高于地面的天空范围内 工程师精准控制空中飞艇飞行。The engineer precisely controlled the airship's flight in the air. Lesson 449, 统筹攻坚 · 文武兼修与科学攻坚 · Cultural Elegance & Scientific Frontiers |
| 太空 | outer space 指地球大气层以外的宇宙空间 深邃太空孕育探索梦想。The vast reaches of outer space nurtured dreams of exploration. Lesson 490, 风雨担当 · 仰观苍穹与敏学笃行 · Cosmic Vistas & Earnest Inquiry |
and 2 more in the catalogue.
Characters that share the sound part 工
Written with the same phonetic, so their readings tend to rhyme with each other.
Characters that contain 空
More characters with the radical 穴
All 6 of them, and what the radical means, on the 穴 radical page.