by now和so far的时态
by now和so far的区别by now表示的意思为到目前为止，但是后面没有要加消极信息的那一层意思,也没有严格的时间点或地点的要求；so far意为如此程度、迄今为止，表示时间点或地点，后面的句子一般用完成时。
She\'ll have had the results by now.
她现在应该知道结果了。
She would be in bed by now, as like as not.
这工夫她很可能睡了。
If you think about it, those children must be at school by now.
想想吧，那些孩子现在一定在学校了。
If he started out at nine, he ought to be here by now.
他如果九点出发，现在应该到这里了。
By now the passengers were getting browned off with the delay.
此时乘客们对延误已开始感到不满。
There should be some snowdrops out by now.
现在应该有雪花莲开放了。
By now all logic had gone out of the window
到这时根本就不讲什么逻辑了。
She\'s a very sweet woman, as you no doubt know by now.
她是一个非常温柔的女人，你现在肯定知道了。