Carol and Susan are very good friends. They are in the same 1 at school and they often visit 2 home at weekends( 周末 ). Now they are 3 eight years old. Carol's mother has got a new baby. Carol is very 4 to have a little sister. So she is always talking about her to Susan. At first she is very 5 in the new baby because she doesn't have any brothers or sisters. But 6 some time she begins to get tired of Carol's endless talking( 喋喋不休地谈论 ) about it. She also fells a little jealous( 嫉妒 ) of her friend. One morning when the two girls 7 in the school ground, Carol says to Susan, "Do you 8 , Sue, my baby sister has put on nearly half a pound in weight( 体重增加了半磅 ) this week." "That is not very 9 ." answers Susan. "I know a baby and he put on ten pound a day." "Oh, that can't be 10 ." answers Carol laughingly. "Whose baby is it?" "An elephant's." says Susan.