__________ our earth, or else it will be no longer fit for us to live on.
You ________ pay too much attention to your reading skill, as it is so important.
In such dry weather, the flowers will have to be watered if they ____________
It is the protection for the trees___________ really matters, rather than how many trees are planted.
We can’t go on with the experiment because the computer_________.
The two sides have finally___________, though some small differences still exist.