._____your son recovers and your daughter passes the college entrance examinations, you will have nothing to worry about.
—I left my handbag on the train, but luckily someone gave it to a railway official. —How unbelievable to get it back! I mean, someone ______ it.
Mother ______ him not to smoke, but he wouldn’t listen.
______ more and more trees cut down, many animals and insects are dying out.
Could it be in the place ______ we visited yesterday ______ you left your book?
Although the number of competitors ___ limited, a number of our classmates ___ eager to take part in it.