build onto
phrasal verbbuild something on | build something onto something
- to add something (for example, an extra room) to an existing structure by building
在（已有建筑物上）增建某物 - They've built an extension on.
他们进行了一项扩建。 - The new wing was built onto the hospital last year.
医院的新翼楼是去年增建的。
- They've built an extension on.