positive cause的用法和样例：
例句
- The actual cause of melasma is unknown, but it is known to be related to both hormonal levels and exposure to sunlight.
黄褐斑的实际原因还不清楚，但它是已知的有关这两个激素和暴露于阳光下。
positive cause的相关资料：
临近单词
positive cam
positive
positively charged liquid film electrode
positive-displacement expansion engine
POSITIVE CLUTCH PISTOL GRIP SCREWDRIVERS
positive deviation and negative deviation
positive pressure central air conditioner
Positive Combat Identification Task Force
positive occipital sleep transient sharps
positive and negative feedback regulation
positive definite Hermitian inner product
positive infinitely variable driving gear
