如题:现有A和B两人,A和B在早上与Tina见了面,然后与Tina分别。之后A和B在一起讨论Tina(此时Tina不在场)。如果要说Tina是个很漂亮的女孩,是说"Tina is a beautiful girl."还是"Tina was a beautiful girl."?
同样的,A和B两人之前去上海游玩,现在回到家乡后讨论上海,如果要说上海是个美丽的城市,是说"Shanghai is a beautiful city."还是"Shanghai was a beautiful city."?