________ London many times, but he knows little about the city.
| A．Having been to | B．Though he has been to |
| C．He has been to | D．He has gone to |
Scientists have created the world’s smallest "snowman",_____ about a fifth of the width of a human hair．
| A．measures | B．measuring | C．measured | D．to measure |
—Late again! Where _____?
—Sony, I in the heavy traffic, or I would have been here earlier．
| A．were you; have got stuck | B．have you been; have got stuck |
| C．were you; got stuck | D．have you been; got stuck |
—Do you know why the teacher asks for me?
—He wants you to _____ your absence last night．
| A．account for | B．call for | C．send for | D．reach for |
—What does the sign over there read?
—"No person smoke or carry a lighted cigarette, cigar or pipe in this area．"
| A．shall | B．may | C．must | D．will |
—Is that Dec．21,2012 is the end of the world true?
—Definitely not, but ______ must be paid to global climate change．
| A．contact | B．care | C．attention | D．influence |