The two picture illustrate vividly......
In the first drawing .....
while in the second one ...
why does this pheonenom appear....
It is....that...
To get a sense of that ,we must turn first cause for it.....
.......because .......as....
If you push the analysis futher you will see that....,thus doing...
there is one more reason that owing to ...
what would our society be like if there were no ....
It is adj that .....,so the top priority task for us to set about is to ....
Ous life abounds with examples in point ,as evidenced in.....
Pherhaps ,it is high time for us to tackle the question in no half-hearted manner.