1. 飞机   boat   train   taxi, cab   airplane   Hint Half-n-half Clue   2. 自行车   ship   ferry   bicycle   train   Half-n-half Clue   3. 汽车   limousine   taxi, cab   ship   car   Half-n-half Clue   4. 出租汽车，小室   motorbike, motorcycle   car   truck, lorry   taxi, cab   Half-n-half Clue   5. 火车   bicycle   ferry   train   ship   Half-n-half Clue   6. 轮渡   limousine   ferry   motorbike, motorcycle   train   Half-n-half Clue   7. 直升机   motorbike, motorcycle   helicopter   limousine   airplane   Half-n-half Clue