Hi my teachers, Could you please correct my essay? Thank you.

Topic: Topic: write a classification essay to discuss about the advantages and disadvantages of different kinds of families in Viet Nam.
From primitive historic of human, the period existed groups of people living together. This is the base that leads to the foundation of the structure of family in the human society nowadays and it is not an exception in Viet Nam. There are many kinds of families, but based on the number of generations in the family, we can divide families in Viet Nam into three major groups: families of one generation, families of two generations and families of three generations. Each group has different structure and its own advantages and disadvantages.
The first group, the families of one generation that established when two people have got a marriage but they still have not had a child. Almost families in this group have not had a child because they have just married so they need time to have a birth. But some other families, either husband or wife has not the ability to produce a birth and they can be very disappointed. In Viet Nam, this group of families of one generation accounts only about ten percent. The advantages of this group of families are the couple have much time to take care of each other, the wife have not to stay at home to take care of a child so they both can do their jobs to earn money. But in the house, it is only having two people living together without a smile of children so sometimes they feel very boring.
The second group: families of two generations that families have parents and children in the house. There are two types of families in this group: the nuclear families and the single-parent families. The nuclear families that have both parents account about seventy five percent in Viet Nam. The wives in these families always stay at home to do households works and take care of their babies. The husbands usually do their jobs to earn money for the family. There are three advantages of these families: parents can raise children better than other kinds of families, the capacity of finance is good and everyone in family always feels very happy about their family background. But in some families, is called single-parent families, there is only either father or mother living with their children. There are many reasons for this such as: parents of children divorced, or one of parents died. It is a sorrow of children so they can feel unconfident or unhappy as other children do. They need many encourages and motivations from their relatives.
The last group of families is called extended families or the families of three generations. In these families, there are three generations living together: grandparents, parents and children. In these families, grandparents always give their children and also parents helpful advices to deal with life problems. But sometimes, the view of grandparents can be out of date. The disadvantage of this kind of family is sometimes grandparents and parents have different views to raise their children because of the difference of two generations. In Viet Nam, this group of families accounts just about five percent of families.
To summarize, there are many types of families in Viet Nam. They can be divided into three major groups based on the number of generations in the families: the families of one generation, the families of two generations and the families of three generations. Each group of families has different structures and its own advantages and disadvantages. The most common families is the families of two generations that is called nuclear families, after that the families of one generation and the last is the families of three generations.

TOEFL listening lectures: An organism that generates internal heat is called what?

Hi, your essay is pretty good. You do have quite a few minor errors though and some of your sentences do not sound very natural.

Thank my teacher. I reallised what I am wrong in my essay, but could you recommend me some alternative sentences that can replace my odd sentences? . Thank you.
Best regards.