这件事成了导火索。
This matter became the fuse.
fuse (for explosive)
Every character draws itself, stroke by stroke. Then grab the brush: trace it yourself and hear the word when you finish.
Nice writing!
Chinese words snap together like bricks. Every word below shares a character with this one, so you are already halfway to knowing it.
这件事成了导火索。
This matter became the fuse.
导火索已经点燃了。
The fuse has been lit.