New ways have to be found to _______of waste materials and poisonous gases so that we can have cleaner surroundings
—Volunteering is becoming popular in China .—Yeah, people are now aware that helping others is helping themselves.
Most students expect ____more review classes before the exams.
—I should have spent more time on English, otherwise I wouldn’t have failed in the exam. —You are right. .
As we all know, surfing_____ Internet has now become _____popular means of obtaining information.
—The party is so great!—Yes, but Johnson, we’ve got to go home. _______—Thank you. See you later!