13. The pleasant feeling can strengthen your confidence in whitening your skin.
愉悅的以情可以增強你美白的信念。
還能這樣說：
Having a good mood can bolster my belief to get a whitening skin.
The pleasant feeling can make you believe that your skin can be whitened.
應用解析：
whiten one's teeth 使牙齒潔白；
whiten cloth 把布漂白
14. It it a common sense that some vegetables are naturally cosmetic products.
某些蔬菜是天然的美容產品，這是一個常識。
還能這樣說：
That some vegetables are natural beauty products is a common sense.
Certain vegetables are natural cosmetic ingredients, which is a common sense.
應用解析：
sixth sense 第六感，直覺；
stand to sense 有道理，合乎情理
15. Cosmetics have side effects.
化妝品有副作用。
還能這樣說：
There are some side effects in cosmetics.
Cosmetics have harmful effects on skin.
16. Facial massage can whiten the skin.
面部按摩可以美白肌膚。
還能這樣說：
Massaging the face can make your skin white.
Give a massage to the face can whiten the skin.
17. Before going out, please remember to daub sunscreen cream to protect your skin.
出門前涂抹防曬霜可以保護肌膚。
還能這樣說：
To paint some sunscreen cream can protect your skin before you go out.
It will prevent your skin to smear sunscreen cream before you go out.