Chinese is a very complex and diverse language. There are several different dialects of Chinese used all across China, as well as thousands of different written characters. There are also several different words found in Mandarin Chinese that have no real equivalent in the English language. However, the following words would definitely make great additions if they were added to English!
Ma la is a combination of the characters that mean "numbing" and "spicy". This word is meant to describe the disorientation that can come over people when they eat a particular dish. Traditional Chinese cuisine has an intense spiciness not often found in the foods native to most English-speaking countries, so it makes sense they would have their own word for this sensation!
Huanying guanglin is interpreted by English speakers as simply meaning "welcome," but it actually goes deeper than that. The first part of the word literally translates to "I meet you with joy." The second half combines characters that mean "light" and "to arrive." More than a greeting, the term is meant to convey that the arrival of the person being greeted is a special event. Talk about a warm welcome!
Ti tie is a word used specifically for family members. It is a word that conveys a sense of the deep respect the members of a healthy family have for one another as they take care of each other and support each other throughout life. It's a unique word for the unique consideration that family members tend to have for one another.
Wei wu wei
Wei wu wei is a phrase that conveys a concept found in Taoist philosophy. We wu wei, or "the action of non-action," describes acting in accord with nature or particular circumstances. At first it appears as if the person acting is actually not doing anything at all, when really, they are acting with the flow of things and behaving in harmony with whatever is around them.