What's on the screen?It there ( ) ad for a new film?为什么括号里用a?

What's on the screen?It there ( ) ad for a new film?为什么括号里用a?
What's on the screen?It there ( ) ad for a new film?为什么括号里用a?

What's on the screen?It there ( ) ad for a new film?为什么括号里用a?
答案：B ad的读音是：[ d] 开头的是元音音素,所以冠词用an.更上一层楼!请记得采纳,B