Pool experts have determinded the proper levels of chemicals that must-------in pool water to protect the swimmers from infection and the equipment-------corrosion and damage.Chlorine keills harmful organisms,but it won't work properly if the alkalin

来源：学生作业帮助网 编辑：作业帮 时间：2024/11/15 19:39:39
Pool experts have determinded the proper levels of chemicals that must-------in pool water to protect the swimmers from infection and the equipment-------corrosion and damage.Chlorine keills harmful organisms,but it won't work properly if the alkalin
xSMO@+{]DcD¥M&ػrKW@J+R@4BӐ E3^]'R/;o߼78 /}PPPT>umƋE+`YtZ&* D|dW

Pool experts have determinded the proper levels of chemicals that must-------in pool water to protect the swimmers from infection and the equipment-------corrosion and damage.Chlorine keills harmful organisms,but it won't work properly if the alkalin
Pool experts have determinded the proper levels of chemicals that must-------in pool water to protect the swimmers from infection and the equipment-------corrosion and damage.Chlorine keills harmful organisms,but it won't work properly if the alkalinty of the water is too----.If the calcium content of the water is inadequate,the water will leach calcium from the walls of the pool,------them
1.A.maintain B.be maintained C.have maintained D.be maintaning
2.A.by B,from C.for D.of
3.A.low B.below C.under D.beneath
4.A.have weakened B.is weakening C.weakening D.weakens

Pool experts have determinded the proper levels of chemicals that must-------in pool water to protect the swimmers from infection and the equipment-------corrosion and damage.Chlorine keills harmful organisms,but it won't work properly if the alkalin
1.选B.这里是一般的情况.maitain维持,保持.游泳池中的学药品的含量必须保持在一个恰当的水平.在这里要用被动语态,是人类保持其含量.
2.选B.and the equipment-------corrosion and damage与前一短语to protect the swimmers from infection 结构是一样的,只不过是省略了一些相同的词而已.
3.选A.如果水中碱的浓度太低,它就不起作用了.
4.选C.表示伴随动作.

BBAC

BBAC

Pool experts have determinded the proper levels of chemicals that must-------in pool water to protect the swimmers from infection and the equipment-------corrosion and damage.Chlorine keills harmful organisms,but it won't work properly if the alkalin some experts have gone further是什么意思 pool pool pool they wanted to have an i pool首字母填空 Many experts have ____ ____ about tsunami.对于海啸,许多专家都有独特的见解. foreign experts 合并I would like to have a swimming pool.I can swim in the swimming pool.成一句不能有标点符号!格式好像是 I would like to have a swimming pool＿＿ ＿＿.后面的我忘了, We have fun in the swimming pool.的同义句We__ __in the swimmingpool. There have a lot of people in the swimming pool 这句话错在哪 there have a lot of people intheswimming pool是哪个单词错 I have always been afraid of the deep end of the swimming pool We want to have a _ (swim) pool in our house what great fun the girls have ________(swim) in the pool 英语翻译：pool pool是什么意思 pool是什么意思