Don’t cross your bridges before they’re hatched.
The Leisure Hive

Well, be to fair, I did have a couple of gadgets that he probably didn’t, like a teaspoon and an open mind.
The Creature From the Pit

First things first, but not necessarily in that order.

I’ll have another pint… ginger pop please.
The Android Invasion

Oh please, don’t call me human, just “Doctor” would do very nicely, thank you.
Revenge of the Cybermen

It’s the end… but the moment has been prepared for.

Well, you see, Mr Scarman, I have the advantage of being slightly ahead of you. Sometimes behind you, but normally ahead of you.
The Pyramids of Mars

You may be a Doctor, but I’m the Doctor. The definite article, you might say.

Guard of honour? You’re not fit to guard a jelly baby! Would you like a jelly baby?
The invasions of time

Unless we work very closely together we could be here until the crack of doom.
Warriors’ Gate

The very powerful and the very stupid have one thing in common. They don’t alter their views to fit the facts. They alter the facts to fit their views. Which can be uncomfortable.. if you happen to be one of the facts that needs altering.
The Face of Evil

Excuse me, can you help me? I’m a spy.
Genesis of the Daleks

It seems you have a very large rat Brigadier. Maybe you should employ the services of a very large cat?

My Doctorate is purely honorary and Harry is only qualified to work on sailors.
The Ark in Space

You never know when these bits and pieces will come in handy. Never throw anything away, Harry.
The Sontaran Experiment

It may be irrational of me but human beings are quite my favourite species.
The Ark in Space

Well, of course I’m being childish! There’s no point being grown-up if you can’t be childish sometimes.

Ah. Well, you’re a beautiful woman, probably; and Duggan was trying to sum up the courage to ask you to dinner. Weren’t you, Duggan?
City of Death