请问英语里面：This is a bus .中的a应该怎样读呢?

It is a car,That is a ( )too.请问应该填A.CAR B.BUS this is a bus.【变为复数句】 Is this a bus （改为复数句 This is a bus.改为复数. 请问she is a very human person这里的human应该怎样理解呢? This is a library.改错,应该怎样改证? --What is this?--It is a bus.改为复数是什么? 英语句式转换This is a bus.(改为一般疑问句)__________________________?Li P this is a bus.把它改为复数句 Is this a bus!翻译成中文是什么? This is a bus.（改为一般疑问句） This is a bus.改为复数形式的句子