Friends are lost forever more unless he goes to Trenzalore.

Whisper Men

Sorry, mam, so sorry. I think I've been murdered.

Jenny

Clara: So you were a friend?
River: A little more than a friend.

Time travel has always been possible in dreams.

Madame Vastra

I don't know where I am. It's like I'm breaking into a million different pieces and there's only one thing I remember. I have to save The Doctor. He always looks different. Sometimes, I think I'm everywhere at once, running every second, just to save him. Doctor? But he never hears me. Almost never. Having blown into this world on a leaf, I'm still blowing. I don't think I'll ever learn. I'm Clara Oswald. I'm the Impossible Girl. I was born to save The Doctor.

Clara

Doctor Who Season 7 Episode 14 Quotes

Time travel has always been possible in dreams.

Madame Vastra

I don't know where I am. It's like I'm breaking into a million different pieces and there's only one thing I remember. I have to save The Doctor. He always looks different. Sometimes, I think I'm everywhere at once, running every second, just to save him. Doctor? But he never hears me. Almost never. Having blown into this world on a leaf, I'm still blowing. I don't think I'll ever learn. I'm Clara Oswald. I'm the Impossible Girl. I was born to save The Doctor.

Clara