It is not easy to learn English well, but if you ____.You will succeed in the end.
The students expected there ________ more free time before the test.
They tried to prevent the damage ________ their cattle.
His father disappeared, ________ two children and never _______ from again.
Does the way you thought of ________ the water clean make any sense?
In order not to be disturbed, I spend three days _______ in my study.