1 完全没有错 也可以 we mustn't keep water from running.
2 propagate the concept of energy conservation(or saving)
还可以 the concept of energy-saving propaganda
第一句我觉得不应该用完成时啊,没有任何表示过去的意思,而且must't或者must not都是禁止的意思,语气太强了。 We should not leave the water running.
第二句 Publicize the energy-saving concept.