To watch TV series online free, you can check out Alluc, tvDuck, Yidio and some others as mentioned before.
The following will show you a new one — TVonline, which is available for you to watch hundreds of TV series online free directly, without any ads.
On the TVonline.cc website, you can pick up a TV show, such as Breaking Dead, Doctor Who, The Good Wife or some other one, select the episode of any season you like, and click the play button, then you can watch it online free directly.
Up till now, there are over 500 TV series, which you can filter by their names listed on the "All Shows" page, and you can also search for by entering their names.
All the videos are played via the Flowplayer software, and can be watched in full screens.
Again, up till now, there are no ads on any page of the TVonline website, though there may be some inside some TV series you are watching, which is better than Alluc, tvDuck, Yidio or any other video website with ads.
With over 500 shows and without any ad, TVonline I think is best website for you to watch TV series (in English) online free — at least for now, do you think so?