I met the teacher in the street yesterday ________ taught me English three years ago.
Alice, bent ______ losing weight, increased the time of exercise to three hours______ a time.
—What time do we have to be at the gate of the museum? —______ the visitors begin to check in.
—Bad news? —If you ______ know, Li Na got defeated again in the first round!
All the government leaders and policemen in Thailand must see to ______ that every citizen should stay safe and sound in the terrible flood.
The time he has devoted in the past ten years ________the disabled is now considered _______of great value.