Depend on us, nowhere else __________ a better service.
We can’t figure out ______ quite a number of insects and birds are dying out.
______ environmental damage is done,it takes many years for the ecosystem to recover.
----- I'm going to San Francisco for a couple of days.------ ________. I wish I could get away for a while.
It’s surprising that your brother _____ Russian so quickly—he hasn’t lived there very long.
According to scientists, our mental abilities begin to ___ from the age of 27 after reaching the highest level at 22.