«Yes, why didn’t I think about it?» The advice of his wife surprised David.

«Okay, I’ll try,» he said coldly and hung up.

He looked around the laboratory, thinking about a possible candidate, and the first person who caught his eye was Marina Aleksandrova.

The teaching assistant was patiently explaining a task to a student. It happened frequently during laboratory work. Lazy or light-minded students did not prepare for the lab, and did not know what was required or how to go about it.

Sometimes the students asked such senseless questions that they astonished David, but Marina listened to them without irritation and peacefully answered.

The professor came close and addressed the student. «You should have read it at home!»

The student made a plaintive face and started making excuses.

«It’s okay.» Marina glanced at David, and turned to the student again. «Did you understand? If you have any questions, I’ll be glad to help.»

The student walked to the lab table, and David shook his head. «I’m simply amazed that you have the patience to explain the same things again and again.»

«I was the oldest child in my family,» Marina answered calmly looking at him. «I’m used to being patient.»

Her odd gaze mixed up his thoughts.

«What strange eyes she has.» For the first time in their communication David noticed it.

Transparent gray-blue, they looked like pieces of frozen water screening her emotions, hiding her thoughts. It was impossible to determine what she felt or what she was thinking about.

«It’s not a girl, but a puzzle,» thought David.

«I’ve never seen you smiling,» he wondered. «Why?»

She didn’t reply.

«I have a problem,» a student interjected, and David forgot what he wanted to ask.