I need it when I want it 这句话怎么理解

I need it when I want it 这句话怎么理解 I need it怎么读 It nothing eles I can say.Just do want you want.这句话怎么翻译? The last thing I want to know is when I can get it.这句话说得对吗wh i need it most I badly need it. Love me when I deserve it least,as that is when I'll need it When I came back it is raining 这句话对吗? 求首歌:If you want it,baby,I got it.If you need it,baby,come ge 求教I don’t really need it与I don't really want it区别~ i want it the I tremble at the very thought of it.怎么理解,帮我分析一下这句话