Why do some experts consider lying a milestone in a child's development? A: It shows they have the ability to view complex situations from different angles. B: It indicates they have an ability more remarkable than crawling and walking. C: It represents their ability to actively interact with people around them. D: It involves the coordination of both their mental and physical abilities.

What have researchers found out about people's earnings? A: They are closely related to people's social status. B: They have to do with people's body weight and shape. C: They seem to matter much less to men than to women. D: They may not be equal to people's contributions.

Paradoxically, mental health is still given inadequate attention in public health, in spite of the high levels of violence, poverty and social exclusion that contribute to worse mental and physical health outcomes for people with mental health disorders.

Social networks are A: The website which society provides for people to use B: A support system government provides for poor families with C: A support systems company provides for their employees who are suffering from difficult situation with D: Relationships among persons in a society E: Mutually supportive relationship between the government and enterprises

Besides damaging people’s ability to do their best in sports, lack of sleep has also been linked to _______ troubles, such as feelings of sadness.