. After school, the students came home, ________.

When the building burns, the firemen will arrive at once and ______ the fire.

Hi, let’s go skating.—Sorry, I’m busy right now. I ___________ in an application form for a new job.

They are looking forward to _____________ to the lecture by the famous professor.

___ finding solutions, it isunthinkable to solve all the problems the same way throughout the country