混合砂浆由（）拌和而成，强度较高，和易性和保水性较好，适用于砌筑地面以上的砌体。
A.水泥
B.石灰膏
C.砂
D.水
E.麻刀
参考答案：A, B, C, D
解析：砂浆按其成分有水泥砂浆、石灰砂浆和混合砂浆等。水泥砂浆属水硬性材料，强度高，适合砌筑处于潮湿环境下的砌体。石灰砂浆属气硬性材料，强度不高，多用于砌筑次要的建筑地面上的砌体。混合砂浆由水泥、石灰膏、砂和水拌和而成，强度较高，和易性和保水性较好，适用于砌筑地面以上的砌体。
| 完形填空。 | |||
| In many classrooms, it's not 1 to find students spinning (旋转) their pens 2 they listen to their teachers. Pen-spinning is also popular 3 Japanese students. It is a form of entertainment. Recently, a pen-spinning competition was held in Tokyo, Japan. Ryuki Omura, a 16-year-old high school student, became the first pen-spinning 4 . 276 people took part in the competition. The came from different age groups. Some were students 5 some were office workers. First, they 6 the videos of their pen-spinning skills to the organizer's website. Then some of them came to the last round in Tokyo. 7 of them had 30 seconds to show their skills in front of 400 people, 8 reporters and fans. Omura took a pen from his little finger to the rest fingers, then to his palm (手掌) and the back of his hand. His wonderful show made him 9 the champion. Omura said he began learning pen-spinning only about 14 months ago. He did 10 in the competition. If you like to spin your pen, you can practice it in your spare time. But when you are in the class, please don't do that. | |||
|