It is necessary for students ______ good studying habits.
—Millie, how long have you __________ this book? —For over a week.
—Excuse me, could you tell me __________? —In ten minutes.
Computers of this kind __________. They are out of stock (脱销) now.
My teacher has given me lots of __________. They’re very useful.
—Do you like tea or coffee? —Coffee. I prefer coffee __________ milk.