The new machine, if 　　　 properly, will work for at least ten years.

St Petersburg, is a very beautiful city, was once called Leningrad.

__ articles for ourwall-newspaper these three years, and he _____ about forty articles.

Don’t complain all the time. If you want to do it, please go on.

It __________ Tom that parked the car here, as he is the only one with a car.