By the 2030s most people can ________ to live at least 80, which is a big leap for mankind.
Only by practicing every day ___________ English well.
Only when 1 was fourteen__________the importance of study.
Only after the plane had taken off _________ that he missed his parents so much.
Only when I left my parents for Italy __ how much I loved them.
So much of interest ___ that most visitors simply run out of time before seeing it all.