[答案]
Iwanttosendsomepostcardsinthepostoffice.
[解析]
首先根据所给词汇及标点,可确定组合的句子为一般现在时的陈述句,组合的句意:我想在邮局寄一些明信片。I我,作主语,放于句首;want to send some postcards想寄一些明信片,是固定搭配"want to do sth",放于主语后;in the post office在邮局,地点状语,放于句末,结合整句及英语表达的习惯作答。
故答案为:I want to send some postcards in the post office.
[点评]
本题考查了"陈述句肯定形式,",属于"常考题",熟悉题型是解题的关键。