The painting is .so valuable that it is difficult to calculate____ its price would be.A that B. which C.what D.\
____has been said before, it is not easy to learn a foreign language.
Tim Bemers-Lee is generally considered ____ the World Wide Web, on which all the information is shared by all.
Was it in this very room ____ he made up his mind ____ he should break away from his family?
Later they discovered, ____ was news to him, that Pamela was the headmaster’s daughter.
I shall always ____ your friendship greatly for friendship is more important than money.