Have you ___________ been to Beijing —Yes. But only once.

I don’t know now.— Her father says she is a little better.

the works of Leonardo da Vinci, theLouvre Museum has more than 6,000 other European paintings, ranging fromthe13th century to the 19th century.

I didn’t know it _______ you told me.

Modern plastics can _________ very high and very low temperatures.