to extend

• 蔓延滋长

  grow and develop

• 火势蔓延。

  The fire is spreading.

• 火势蔓延到邻舍

  the fire has spread to the house next door

• 战火蔓延

  the flames of war are spreading

• 经济危机的蔓延

  the spread of the economic crisis

• 防止传染病蔓延

  prevent the spread of infectious diseases