The reason for constructing the buildings from wood is probably that ideally proportioned straight and slender timber was available in large quantities in Scandinavia's vast pine forests.
2019年12月六级真题（第一套）听力 Section C
柯林斯高阶英汉双解学习词典释义
COMB in ADJ-GRADED
（和副词一起构成形容词）表示“成比例的”，“协调的”，“均衡的”
-proportioned is added to adverbs to form adjectives that indicate that the size and shape of the different parts of something or someone are pleasing or useful.