Barack Obama, who came into _________ power on January 20, 2009, was awarded _________2009 Nobel Peace Prize.
The day________ he was looking forward________ in the end.
—Who ________ it be that is knocking at the door? —It________ be Mother, but I’m not sure.
If you cheat in the exam, you could hardly________ it.
He once studied in Zhejiang University, ________he went abroad for further study.
More attention should be paid __________ English.