提出建議

It's high time that we put an end to the trend.

There is no doubt that enough concern must be paid to the problem of ...

Obviously,if we want to do something ... , it's essential that ...

Only in this way can we ...

推測后果

Obviously,if we don't control the problem,the chances are that ... will lead us in danger.

No doubt,unless we take effective measures,it's very likely that ...

It's urgent that immediate measures should be taken to stop the situation.

論證類型

From my point of view,it's more reasonable to support the first opinion rather than the second.

I can not entirely agree with the idea that ...

As far as I am concerned / In my opinion, ...

I am greatly convinced that ...

Finally,to speak frankly,there is also a more practical reason why ...