The painting is .so valuable that it is difficult to calculate____ its price would be.A that B. which C.what D.\
–Did you enjoy yourself at the party? --Yes, I’ve never been to ______one before.
Peter’s jacket looked just the same as Jack’s, but it cost ______his.
Not until I came home last night _____to bed.
_____twice, the postman refused to deliver our letters unless we chained our dog.
She had just finished her homework _____her mother asked her to practice playing the piano yesterday.