1. She was going to talk with slides about our town amid eighteenth century. 她要用幻灯片讲我们镇子十八世纪的事。
2. The strings are now metallic, but in the sixteenth, seventeenth to eighteenth century, they would have been made out of cat or sheep gut. 弦现在是金属的，但在十六、十七、到十八世纪，它们是用猫肠或羊肠制作的。
3. During the seventeenth and eighteenth centuries, the entire site became covered with a layer of hard grey clay, which minimised further erosion. 在十七世纪和十八世纪，整个遗址被一层坚硬的灰色粘土覆盖，这极大减少了进一步的侵蚀。
4. The siege is now in its eighteenth day. 围困现在是第18天了。
5. We got engaged on my eighteenth birthday. 我们在我18岁生日那天订婚了。
