The Leaning Tower of Pisa is so great --ancient building.是填a\an\the\\

The Leaning Tower of Pisa is so great --ancient building.是填a\an\the\\
The Leaning Tower of Pisa is so great --ancient building.是填a\an\the\\

The Leaning Tower of Pisa is so great --ancient building.是填a\an\the\\
The Leaning Tower of Pisa is so great 【an】ancient building
结构是
【so +adj +a/an+n】
这边ancient是原音,所以用an