The old man looks healthy.—Yes. He________ some running after he getsup.

He is believed____________ in at his office on his way home

Cloning plants is straightforward cloninganimals is very complicated .

(2013·济南二模)It was during the Ming Dynasty ________ the Great Wall was repaired and extended to take on the appearance it has today

Mr Smith will not be able to attend his son’s wedding ceremony, because he ________ an important speech.