-- What’s wrong with your pen?-- The ink ___________ come out.

(2013·潍坊市高三二模)Sometimes smiles ________ be false, hiding other feelings like anger, fear or worry.

Who ________ a lady like Susan Boyle, once an ordinary woman in Scotland, would achieve overnight success at Britain’s Got Talent Show?

—When I first got to Harvard, my awkward English brought me great trouble.——Oh, dear, it _______a struggle for you to keep up with other students.

—It's no easy task to catch a ticket on a website that receives 1 billion clicks daily.—I can't agree with you more. There ________ be errors for every single step.