To keep gums healthy , practice good oral hygiene .

想保持牙龈健康，就需要良好的牙龈卫生。

The study tests what 's called the hygiene hypothesis .

这项研究验证了所谓的卫生学假说。

Breast-feeding advice , food supplements and better hygiene all make a big difference .

母乳喂养指导、食物进补以及更好的保健都会产生显著变化。

He is a photogenic monster with good hygiene .

他是一个有着良好卫生习惯又上镜的怪物。

Develop a good daily oral hygiene routine .

养成良好的每日口腔卫生习惯。