粗骨料级配的好坏，对保证混凝土的和易性和强度有作用，但对耐久件无意义（）

Directions:

Write an essay of 160-200 words based on the following drawing. In your essay, you should

1) describe the drawing briefly,

2) explain it’s intended meaning, and

3) give your comments.

Your should write neatly on ANSWER SHEET 2.