啦
lā · HSK 6
indicating excitement/doubt/comfort/etc.
📢 LA! = the sound you belt out to announce news, like a fanfare
Think of someone bursting through a door yelling LA! to share exciting gossip. The mouth-open 口 on the left is doing the talking, 拉 on the right gives the LA sound. It tags the end of a sentence the way a drumroll tags a reveal.
啦 — mouth radical 口 + 拉 (lā, pull)
啦 is a modern phono-semantic compound. The mouth radical 口 marks it as a spoken particle, while 拉 (lā) supplies the sound. It is a fused contraction of 了 + 啊, used at sentence end to soften statements or mark a change of state.