小苏打可用于治疗胃酸（主要成分是盐酸）过多，其原因是（用化学方程式表示） ____．
小苏打可用于治疗胃酸（主要成分是盐酸）过多，其原因是（用化学方程式表示） \_\_\_\_．
表示
There were a _____ number of students on the playground.
There were a \_\_\_\__ number of students on the playground.
D的化学式是____，D溶液显碱性的原因是（用离子方程式表示）____．
D的化学式是\_\_\_\_，D溶液显碱性的原因是（用离子方程式表示）\_\_\_\_．
He has come to work for a local newspaper about ten years ago, when he graduated from Peking University.
He has come to work for a local newspaper about ten years ago, when he graduated from Peking University.
The entire structure cost more than $2.5 million to build at the time.
The entire structure cost more than $2.5 million to build at the time.
“Can your brother and sister understand the English teacher?”“No, _____ of them can.”
“Can your brother and sister understand the English teacher?”“No, \_\_\_\__ of them can.”
Young boys and girls stood on _____ sides of the street to welcome the president from Africa.
Young boys and girls stood on \_\_\_\__ sides of the street to welcome the president from Africa.