"What's that?"

"Hmm?" The Doctor looked up from the gadget he was probing with his sonic. Rose was hovering near the controls of the TARDIS, leaning in to examine something. "What?"

Rose shifted over a bit so he could see that she was looking at the sticky notes he'd attached absentmindedly to the monitor. "These are words, aren't they? Why can't I read them? Is the TARDIS's translator malfunctioning?"

"TARDIS won't translate that," he said shortly, wrestling with the device. The sonic was emitting a worrying high note and it was taking all of his attention. If he didn't fix the issue within a few seconds- there! He made a mental note to not do… whatever it was that had caused that… again. Also not to tell Rose about this.

Rose mulled his words over for a moment as he checked that the thing in his hands was harmless. Then: "Is that in your language, Doctor?"

It was a while before he answered. Several unhappy realizations passed through his head in rapid succession. "Yeah," he said finally. "Yeah, it is."

"It's beautiful," she said, examining the intricate circles and overlapping designs. "What's this one say?"

He peered at the note Rose indicated. From his position, it was a little difficult to make out the letters, but he got the gist of it. "That one… That's to remind me to hook the external phone into the main console at some point. You know, that's really a good point, I'd forgotten that I've been meaning to do that… How long has that note been there?"

Rose laughed at his troubled expression. "What about this, here?"

The Doctor stood and walked over to her, still clutching the broken appliance but tucking away the sonic screwdriver. He pulled out the spectacles he didn't really need and bent toward the note. "Oh, no. Can't tell you that one. It's a surprise."

"Really." Rose raised an eyebrow and grinned at him sideways. "Very mysterious."

"Well, I can't give away all my secrets," he said, giving her the smile only she could draw out of him. "Where would I be then?"

"Could you teach me?" she asked suddenly, and his hearts stopped for a second. "To read it, I mean. Would you teach me to read this?"

His mouth had gone dry. Someone else knowing Gallifreyan… he hadn't realized how much he had wanted that since the Time War. Somewhere out there, he was sure, some embassy member, or ambassador, or something would probably know how to speak it. But that wasn't the same as being able to speak his own language with someone he cared about. It couldn't compare to leaving casual notes in circular Gallifreyan. There was nothing that could come close. If he were to teach Rose…

"No crack about only wanting to spoil the surprise?" Rose said, and he knew his silence was worrying her. "Doctor, would it be alright? I mean, there isn't some kind of rule that only Time Lords can know it, or-?"

"Nah!" said the Doctor, so suddenly that he saw her jump. "Besides, when have I ever been one for the rules?"

He winked and she blushed. "So- so that's a yes?"

"Sure, when d'you want to start? Is now good?"

"You don't have plans?" Rose teased. "Nowhere else to be? No… pressing appointments?"

The Doctor rolled his eyes exaggeratedly. "We're in a time machine," he reminded her. "We'll reschedule. Library this way, Rose! Allons-y!"

"Well, first, you've got to realize that Gallifreyan isn't just an alphabet for transcribing English. It's a language on its own. Really, I ought to be teaching you the language as well, but we'll get to that. Far easier to learn a new alphabet than a new language, yeah?"

Rose smiled at the Doctor. She loved seeing him so excited. And she really was eager to learn his language and his writing system. There was so much she didn't know about his past. The fact that he was bringing her into this aspect of his life meant a lot to her, and she hoped he knew it.

"Sounds good. So we'll be writing English using Gallifreyan letters, then?"

"Exactly. Pull up a chair, here, and watch."

Rose watched the Doctor's hands move meticulously across the page. His ability to draw geometrically precise circles was far beyond anything she would ever be able to do, but she supposed nine hundred years of practice had to help.

The next twenty minutes passed swiftly as he explained the rules of how to arrange the letters into words and then words into sentences. Transliterating English into Gallifreyan was fairly basic, with only a few exceptions to keep in mind, and Rose was sure she could pick up the alphabet pretty quickly.

"Write something for me," Rose said. She wanted the chance to look at him as he was immersed in the act of writing and couldn't notice her staring. She wanted to see his look of concentration, that focused gaze of his when he was giving something his utmost attention, the intensity of his expression that showed the depth of his emotions. And mostly, she wanted him to give her something he'd put effort into. It would feel like proof, though of what she wasn't exactly sure.

The Doctor looked at her with no hesitation, willing to take any request. "What should I write?"

She shrugged, not having thought this far. "Write… show me how to write my name."

He beamed. "Here."

Rose watched him spell it out slowly. At first he paused after every step to explain what he was doing and kept up a steady stream of narration, but after the first few letters he became, as she had hoped, too engrossed for speech. His head bent low over the paper, and she could have sworn the tip of his tongue was peeking out of the corner of his mouth. She couldn't hold back an amused smirk, but he didn't see.

"Now your turn," he told her, pushing the paper toward Rose and handing her the pen. "Go on, just like I showed you."

The Doctor couldn't stop smiling as he watched Rose carefully try to copy down the words he'd drawn for her.

"Ugh. Circles are hard," she muttered. "Got any stencils for beginners?"

"'Fraid not," he said brightly. Which was not strictly true, but he had a better idea. "I'll help."

He laid his hand over hers. "Steady," he murmured, "steady…"

Rose bit her lip as he guided her hand across the page. He felt it was over too quickly.

"Is that it? We're finished? That's my name!" Rose looked to him for confirmation.

"Rose Tyler," he read, nodding. "Beautiful."

He wondered if she knew he didn't mean the writing. Certainly he wasn't looking at it.

"I dunno, I think my hand shook when I was doing that part there." She pointed to a section that looked exactly the same as the rest of it to the Doctor.

"So you want to try again, is that it, Rose? Alright, I think I have time in my… incredibly busy schedule."

Rose smacked his arm. "Someone told me we're in a time machine," she said, and stuck out her tongue.

They spent the rest of the day practicing.

"...where… are… the…" Rose muttered as she sketched. She and the Doctor had taken to leaving small notes for each other on random surfaces, be they practical or silly. This one was a demand to return the misplaced mugs. She had no idea why he'd moved them, but they were gone, as she'd discovered when she'd tried to make a cup of tea.

She knew when he had found it by the note placed over it. She narrowed her eyes and deciphered the strange geometric symbols.

"...whaddya mean 'outside'? I thought we were in the Vortex? Doctor!"

His head popped out from a random corridor. "Yes, Rose?"

"Did you dump the mugs into the Time Vortex?" She put her hands on her hips. "How'm I supposed to make tea with the mugs hurtling through time and space on their own?"

"No, no," he protested, emerging fully to defend himself. He dragged a hand through his hair. "I didn't write that. Can't have done. Haven't dumped the mugs, so I wouldn't have. Pass me the note, would you?"

Rose did so, refusing to give ground. "See for yourself."

He frowned at the paper. "Ah yes, I see now. You've missed something."

"What? What've I missed?"

"The part where we landed," he said with a cheeky grin. "Picnic on the planet of Odlarno. Best picnic spot this side of Yorkshire. Whaddya think?"

Over cocoa, he told her that her Gallifreyan was coming along incredibly well, and she had to ask if the gravity of Odlarno was less than Earth's. (It wasn't.)

When he felt she was ready, the Doctor told Rose she could start learning the language itself. Her face lit up when he said the words, and the first time she said anything in his native language his insides felt like they were melting or burning or spontaneously combusting.

"Rose Tyler," she said hesitantly, and it took everything in his power not to grab her into a hug on the spot. "Am I saying that right?"

"Perfect," he enthused, and Rose beamed.

"What'll you teach me to say?" Her smile outshone the stars outside, and he could more easily breathe in the vacuum of space than without her.

"Anything. Everything," he whispered, and then blinked. "Why, is there something specific you want to know?"

Rose looked at him for a bit. "Nah, we've got time," she said finally.

"Time machine has its perks," he agreed, and nodded.

"That's not what I meant, you daft alien." Laughter trickled through her words and he loved the fact that he could make her laugh so easily and comfortably.

"Hmm? Explain yourself, then," the Doctor challenged her.

Rose went quiet for a little while, no longer able to meet his eyes. He wondered if he'd done something wrong, but: "We've got forever, the two of us," she finished softly. "Haven't we?"

He hoped his smile was answer enough.

But as Rose stood alone on Darlig Ulv Stranden, there was one thing he hadn't taught her to say. One sentence he hadn't said or written. Three words he had not given her.

And now he never would.