[bù rán]
（不是這樣） not so; not the case; no
Actually this is not so.
其實(shí)不然。
I've got to leave a bit early, otherwise I'll miss the train.
我得早點(diǎn)去，不然就趕不上火車了。
Either be there on time, or don't go at all.
要去就別遲到，不然， 就甭去了。
No, it's not as simple as that.
不然， 事情沒(méi)有那樣簡(jiǎn)單。