___ is believed ___ more and more people would fly to the moon in the future.
The item you requested yesterday is no longer available and ________ we are returning your cheque.
I kept looking at the man wearing a pair of glasses, wondering ________.
It was not until last year ________ he got in touch with his father in Canada.
Every morning at a ________ time after breakfast she gave him an hour’s lesson.
________ their service, the workers of the hotel are active in learning English.