框架纵向钢筋的连接应能保证两根钢筋之间力的传递。有三种常用连接方法：【 】连接、【 】连接和【 】。
参考答案：机械 绑扎 焊接
连词成句。用所给的单词组成正确的句子，写在下面的横线上。
1. tall, I, a, tree, green, see
2. is, at, Jenny, pointing, school, red, the, little
3. and, the, Jenny, afternoon, quiet, I, are, in
4. drawing, a, he, picture, is, now
5. on, man, train, this, is, the
什么叫道口的“三标一桩”？
