In China,_____ bus is _____ popular means of transportation.
Receiving the report that the plane crashed, the government took measures .
Newton was sitting under an apple tree ______ an apple fell onto his head.
The clock has just _________ twelve. All the teachers should stop _________ and let the students have a rest.
A thunderstorm is likely to come. Let’s hurry up so as not to __________ it.
Although their new factory building is still under construction, we have already placed order for 200 pairs of shoes.