The decorations on that Valentine's card were cheesy-looking.

cheesy-looking 是由形容词 cheesy 和现在分词 looking 组成的复合形容词。cheesy 来自名词 cheese（奶酪），引申为"俗气的、廉价的"，因为奶酪容易变质发臭。looking 表示"看起来...的"。cheesy-looking 合起来表示"看起来俗气的"。