为了区分内力方向，规定剪力值向上为正，向下为负；弯矩值顺时针为正，逆时针为负。(
题型：判断题
问题：
为了区分内力方向，规定剪力值向上为正，向下为负；弯矩值顺时针为正，逆时针为负。( )
题型：判断题
阅读理解。根据短文内容回答下列问题。
It is 1965. A little boy is at the beach with his parents. He is four years old. The boy is playing near the
water. He walks into the water. His parents aren't watching him.
The water is over the boy's head! A woman sees the boy. The woman's name is Mrs Black. Mrs Black
go
es to the boy. She carries 
him to his parents. "Thank you!" the boy's parents say.
It is 1975 —ten years later. The boy is at the same beach. He is fourteen years old now. He is big and
strong. He is a good swimmer.
A man is in the water. The man can't swim. "Help! Help!" the man cries. The boy runs into the water.
He swims to the man. He pulls the man to the beach. "Thank you. Thank you." the man says.
Who is the man? Can you guess? His name is Mr Black. He is Mrs Black's husband.
How interesting it is!
1. Where is the little at 
first?
___________________________.
2. Are his parents watching him?
___________________________.
3. Who carries the little boy to his parents?
___________________________.
4. Can't the boy swim when he is fourteen years old?
___________________________.
5. Is the man the boy's f
ather?
___________________________.
