A
Nuclear（核心的）Family
53.7% of Canadians live in nuclear families. A nuclear family usually has parents and children. It is also called the traditional family. This kind of family was the most popular in the 1950s and 1960s. Now the traditional family is choosing to have fewer children than in the past.
Single-Parent Family
In this kind of family, there is only one parent caring for one or more children. The number of single-parent families is becoming larger. The environment of single-parent family is not very good for the mental and physical health of children.
Extended（几代同堂的）Family
There are grandparents, aunts, uncles and cousins in this kind of family. Members of the extended family live together for many reasons, such as helping to raise the children, caring for each other and dealing with money problems. The number of this kind of family has increased by 40 percent in the past ten years.
Childless Family
A childless family is the one that choose not to have children. The couple has never had children because of some reasons. Most have thought carefully about whether to be parents but finally give up because they think it wasn’t really right for them. To replace children, childless families usually have pets instead.
21．There are ________ in the nuclear family.
A．only parents B．grandparents and children
C．parents and children D．aunts, uncles and cousins
22．The writer thinks the environment of ________ is not very good for the health of children.
A．the single-parent family B．the traditional family
C．the extended family D．the childless family
23．Which of the following is TRUE according to the passage?
A．The number of the extended family is the largest of the four kinds of families.
B．Now the nuclear family is a family that chooses to have more children.
C．A childless family is a family that chooses to have one child.
D．Members of the extended family can help each other.
