When you ______ a difficult task, try to continue with it and finish it.

ll do the right thing and do what we have to do investigate crimes ______ they exist,” claimed the police officer in chief.

The cars give off a great deal of waste gas in the street.—Yes, But I’m sure something will be done toair pollution.

_______ lucky number you’ve got in the competition!

The comments on the film, ______ this is one example, are very sharp.