We are now in the age of great changes. Everything sometimes ________ before it is felt.

Unfortunately, when I arrived she ________, so we had only time for a few words.

—I failed again in the maths exam. How disappointing!—You          it! You never spend time on your maths study.

It was the second time that we ______ in holding such important parties.

For some time the expert __________ people of the health risks caused by passive smoking. He     says he won't stop until all the smokers around him decide to quit smoking.