I feel very pleasure to board with your family,and i believe it's a great help to improve my English level.Hoping that we'll get along well with each other!I‘m sure it will be a good memory for both of us.
(另:我把最后一句“我想那一定会是我一段美好的回忆!”改成了“我想那一定会“成为我们之间”一段美好的回忆!”,你如果想改回来,就把最后的“for both of us”改成“for me)