___ had they reached the 30th floor ____ they realized that they had forgotten to take the key.
How pleasant the picture is to _________!
Jack went to college last year, _________ to return home until he achieves his goal.
— What’s that terrible noise? — The boys _________ for a party.
Every minute is made full use of _________ our lessons before the exam.
Help is needed for families _________ homes were destroyed during the earthquake.