①From what has been discussed above→
Taking into account all these factors→
Judging from all evidence offered→,we may safely draw/reach/come to the conclusion that.（三个句子箭头后都是we may safely.这句）
②It is high time that we→placed great
→made special
→put considerable →emphasis on the improvement/development/increase of.（中间三中表达方式随便选一种,再加最后箭头后的句子即emphasis on the.就可以了）
③There is little doubt that special attention must be paid to the problem of .
④It is necessary that effective actions sould be taken to.
⑤We must/should call for an immediate action to.
这些句子都可当文章结尾的号召语句使用,我给出的只是句式,因为句子内容要依据文章内容定的,所以你具体情况具体分析修改吧.
祈使句行动吧→Take action!
