www.bbc.co.uk/news/uk-politics-30829222
For one thing you will be giving a greater chance of the Tories and UKIP winning the election due to the fact votes are being taken from Labour and the Lib Dems. You are not taking votes from UKIP, you are taking votes from Labour the party more likely to win the election.
Second my family live in Brighton and the Green Party have been awful there, the rubbish collections...the roads, do not talk about what they done for the motorist in that town.
If you are voting for the Greens, why???