two-by-four

劍橋詞典

a standard size of finished wood used for building that measures slightly less than two inches wide and four inches deep and can be cut to various lengths , or wood of this size
2x4尺寸；2x4的木料（或建材）（用于建筑的成木標(biāo)準(zhǔn)尺寸，略短于2吋寬及4吋深，可切割成不同長度）
You'll need four eight-foot two-by-fours to frame out that wall . 要構(gòu)建那面墻的框架，你需要四塊2x4吋、8呎長的木材。
a two-by-four board 一塊2x4吋板 返回 two-by-four