[1955 Doc Brown]
Y'know Marty, I'm gonna be sad to see you go. You made a real difference in my life. You've given me something to shoot for; I-just... knowing... I'm gonna live to see 1985! Then I'm gonna succeed in this; that- that I'll have the chance to travel through time. It's gonna be really hard to wait 30 years to talk about everything that's happened these last few days... I'm really gonna miss you, future boy
I need to prepare our weather experiment, and you... you need to pick up your mother

[Marty McFly]
Dear Dr. Brown
On the night that I go back in time, you collapse from plutonium radiation poisoning
Plеase take whatevеr precautions are necessary to prevent this terrible disaster
Your friend
Marty

I don't know how I ended up here;
It's so hard to believe
There's one chance and this much is so clear
If I miss it, I may never leave
I'll be stuck in this dream;
Can't wake up, can't get free

Destiny...
I'm not sure what that means
And history...
Well, it's not everything that it seems
Will I be on my way
Or will I have to stay?
But it's always a matter of time...
[Jennifer Parker]
We've been-a waiting a lifetime it seems
For a chance to break through
Now I know all our hopes and our dreams
Are real and about to come true
It's so easy to see
This is all meant to be

[Jennifer, Marty, Both]
Wherever we're going is alright with me
There's no way of knowin' just where that will be
We'll get where we're going eventually
Wherever we're going is alright if you're there with me
It's only a matter of time
Only a matter
Only a matter of time
I may not get out alive
Only a matter of...
Time...