Ifndef
如果未定义
🗣️ 情景例句
And Alexandra brought us a pumpkin pie. Alexandra
Alexandra给我们带来了一个南瓜派。
I've had enough.
我已经吃饱了。
I went downstairs and sat in front of the television pretending to read.
便来到楼下坐在电视机前假装看书。