On account of fuel supplies being finite and many people being wasteful, we will have to install ________ solar heating device in our home.
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 placedorder for 200 pairs of shoes.