2 sentences

1. 这是一个多山的岛屿，人口密度高。

   zhè shì yī​ge duō​shān de dǎo​yǔ, rén​kǒu​mì​dù gāo.

   It is a mountainous island with a high population density.

   Source: CCMatrix

2. 古罗马至少比现在的纽约市人口密度高出六倍。

   gǔ​luó​mǎ zhì​shǎo bǐ xiàn​zài de niǔ​yuē​shì rén​kǒu​mì​dù gāo chū liù bèi.

   Ancient Rome was at least six times more densely populated than present-day New York City.

   Source: CCMatrix