20、It was two weeks before Christmas, and Mrs. Smith was very busy. She bought a lot of Christmas cards __21__ to her friends and to her husband's friends, and put them on the table in the living-room. Then, when her husband came home from work, she said to him, "Here are the Christmas cards __22__ friends, and here are some stamps, a pen and our book of address. Will you please write the cards __23__ I am cooking the dinner?"Mr. Smith did not say anything, but walked out of the living-room and went to his study(书房). Mrs. Smith was very angry __24__ him, but did not say anything either.Then a minute later he came back with a box full of Christmas cards. All of them had addresses and stamps on them."These __25__ last year," he said, "I forgot to post them