I lost my keys, otherwise I ________ comfortably in bed now.
Allen had to call a taxi because the box was ____ to carry all the way home.
—Do you know the most ancient city in China—Xi’an well?—No,this is the first time I ________ here.
Our teacher told us that there ______ no end to learning.
It is said that there are millions of camels in India and _______ of them is growing.
They ask about the things and teachers ______ they still remembered in the school.