Scientists have to work hard to keep ________ with modern discoveries and developments.
Having answered the phone, I couldn’t but ______ what would happen next.
All of us remember the earthquake that ______ Wenchuan in 2008.
Paul had to write a history paper, _____ he couldn’t find time to do it.
They want to know ______do to help us.
I’d like to study law at university ____ my cousin prefers geography.