Time is valuable. We have to _____ every minute of each day.
Everyone has periods in their lives ______ everything seems very hard.
By the time we reach that page, we ___________ twenty lessons of the book.
On hearing the bad news, he got up quickly ______ the lunch unfinished.
The girl looked at me with a _______expression. Maybe the problem was quite ______.
Would you please ______ your statement again? I don’t understand what you were saying.