—You seem to be familiar with London.—I ______ there for three years. It’s great to be back.

Being a teacher always encouraging students to think for themselves, I won't tell them answers until they __________ on a math problem for more than an hour.

Her money ______, the lazy middle-aged woman began to steal others’ money at crowded places, such as bus stops, stations, airports and ports.

You will have to wait for one more week, when the manager _____ back from his trip.

—Why didn’t you answer my phone at 10 am? —I           for my decayed tooth in the clinic.