题目内容
（请给出正确答案）
The heating system has recently been______to make it more efficient.
A．modified
B．changed
C．corrected
D．replaced
简答题官方参考答案
（由简答题聘请的专业题库老师提供的解答）
更多“The heating system has recently been______to make it more efficient.A．modifiedB．changedC．c”相关的问题
Task Two — Topics
A the efficiency of the heating system
B the amount of homework given
C the behaviour of children
D the condition of chairs
E the standard of teaching
F the relationship between parents and teachers
G the lack of job satisfaction
H the motivation of pupils
The central heating system has proved____________(没最初期望的那么有效)
A.be established
B.be sent
C.be covered
What is broken？
A．A mobile phone
B．A window
C．An air conditioning system
D．A heating system
The heating system has recently been ______ to make it more efficient.
A．modified
B．amended
C．altered
D．changed
(25)
A．Though sunshine is free, we still need to purchase fuel to operate a solar heating system.
B．We need to purchase a solar system before we can use the sunshine.
C．If we want to use sunshine for the solar heating system, we must buy fuel first.
D．It's not necessary to buy fuel to run a solar heating system.
How long has it lasted since the heating system stopped working？
A．About two days
B．Nearly seven days
C．About four months
D．Almost fourteen days
A.discussion
B.complaint
C.praise
警告：系统检测到您的账号存在安全风险
为了保护您的账号安全，请在“简答题”公众号进行验证，点击“官网服务”-“账号验证”后输入验证码“”完成验证，验证成功后方可继续查看答案！
