I am a student. ________name is Tom.

Was it because of his short­sightedness ________ he was turned down by the company?—No, it was because of his poor performance.

Guess what Tom has failed in the exam ____second time. —How come He is ___ second to none inEnglish in our class.

Scientists _______ a lot of experiments onanimals, hoping to find and effective way to cure the patients who had AIDS.

Though my grandmother is old, her voice ______beautiful.