—Sure! It ____ by Mozi over 2,000 years ago.
—Maybe, I think.
—It's me. The photo ______ 10 years ago.
—Our computers by a virus, so the engineer disabled(禁用)all of them.
— That's for sure. Trust me!
—Exactly. I have seen it twice.
—Of course. It ____ many times on the radio.
—Really? That sounds cool!
—Yeah.That' s because the G20 Sunmit(峰会)__________ next week, on September 4 and 5.
—It's OK. You_________ plenty of time to decide.