— ____ that you came here yesterday?— By train.
The research is so designed that once __________ nothing can be done to change it.
__________ more attention, the trees could have grown better.
__________ many times, he finally understood it.
(2009·江西) __________ the right kind of training, these teenage soccer players may one day grew the international stars.
(2009·福建) __________ not to miss the flight at 15: 20, the manager set out for the airport in a hurry.