在弄清各部分形状后,根据各部分的形状和它们之间的相对位置,通观全局,就可想象出零件的整体形状。
参考答案:对
阅读理解。
One Sunday afternoon Mr Green and his child, Mary, are in a big shop. Mr Green likes Mary and wants
to buy a new dress for her. Mary doesn't like the new dress. She likes something to eat. So her father buys
two kilos of apples for her, too. Mary also wants to buy some picture-books and colored pencils. There are
many things and many people in the shop. They are men and women, old and young. They all want to buy
something there. The people in the shop are very friendly.
1. It is ________.
A. Saturday
B. Monday
C. Friday
D. Sunday
2. Mary and _______ are in the shop.
A. Mrs Green
B. his father
C. her father
D. her mother
3. Mary likes to buy ________.
A. a new dress
B. colored books
C. apples, picture-books and colored pencils
D. something to drink
焊接梁结构中的锯齿形腹板的齿形是()。
A、等腰梯形
B、等腰三角形
C、正方形
D、矩形