by now： 到目前（时间段）， 所以用作现在完成时或者过去完全时的状语。
例如：
1). I have fulfilled my schedule by now.
2). She has finished her homework by now.
3). They have expected her to come by now.
by now 这个现在是指 到目前为止 的意思。
by now”为什么可以修饰现在完成时？
I had expected to be near my objective
内容全部来源于网络收集，如有侵权，请联系网站删除：QQ：24596024