lǎo / shī / bǎ / lǎo / huàn / dēng / tóu / yǐng / dào / píng / mù / shàng / gěi / wǒ / men / jiǎng / jiě / nà / duàn / lì / shǐ

老师把老幻灯投影到屏幕上，给我们讲解那段历史。

The teacher projected the old lantern slides onto the screen and explained that period of history to us.