acre

计划是每英亩种植10,000棵树。

The plan was to plant 10,000 trees per ___acre.

这个农场今年目标是每英亩种植500棵树。

The farm aims to plant 500 trees per ___acre this year.

一英亩约等于四千零四十七平方米。

One ___acre is about 4,047 square metres.