I don't think the experiment is ___ failure, because it has provided us with ___valuable experience for our future tests.
By nine o'clock,all the Olympic torch bearers had reached the top of Mount Qomolangma,________appeared a rare rainbow soon.
It’s quite warm now.Leaving the heating on all the time ________ electricity.
All her energies are ________ upon her children and she seems to have little time for anything else.
-Brad was Jane’s brother! —________ he reminded me so much of Jane!
In recent years________global warming is becoming ________ concern for people all over the world.