Any day will do? 哪一天都可以？ 
Any messages for me?   有我的留言吗？
Are you by yourself? 你一个人来吗？All right with you?   你没有问题吧？
Are you free tomorrow? 明天有空吗？   
Are you kidding me?   你在跟我开玩笑吧？
As soon as possible! 尽可能快！