demonstration造句

This is a clear demonstration of how technology has changed.
这清楚地表明了技术已有了怎样的进步。

He gave a demonstration of the new technique then and there.
他当场表演了这种新的操作方法.

The book is a demonstration of scholarship without pedantry.
这本书表现出学术水平又不故意卖弄学问.