根据中文提示将下列句子补充完整。 (1)他们正在讨论他们的周末计划。 They are talking about _________ _____________ _________ the weekends. (2)你和你姐姐个子一样高吗? _______ you as _______ as your sister? (3)我将要去超市为我父母买礼物。 I’ll go to the _____________ to buy some ___________ for my ___________ . (4)我父亲正在他的书房里写信。 My father _______ ________ _______ _________ in his study .