Don’t handle the vase as if it ____ made of steel.

一Professor Li, ______the student start at once or wait a while?     一At once.

—The research on the new bird flu virus vaccine is challenging and demanding. Who do you think can do the job?—____ my students have a try?

Tony ____ the invitation, otherwise he would have attended your birthday party. 

"The interest ____ be divided into five parts, according to the agreement made by both sides," declared the judge.