【推荐1】He ______ (serve) in the army for 15 years by the end of last year. (所给词的适当形式填空)

【推荐3】My favourite dish was boiled dumplings ________(serve) with vinegar. （所给词的适当形式填空）

【推荐1】With his work _______ (complete), the businessman steeped back to his eat, feeling very pleased. (所给词的正确形式填空)

【推荐2】The fire, which is thought to have started from the 8^th floor, spread quickly through the tower block on Sunday night, leaving people on the upper floors ________ (trap). (用所给词的适当形式填空)

【推荐3】He found some seeds _________(fold) in a little piece of paper. (所给词的适当形式填空)