Center 1: bring up a bar of two
Step 1 / 3
r: Right inner layer: turn 90°, front face goes up (Written as TR in the textbook)
The top is missing the left and middle spots of its front row. The front has two white pieces in its right column, top and middle.
r lifts the bar. U' turns the two wrong pieces into the right column, r' sends them down to the front.
Step 1 of 3: r. Right inner layer: turn 90°, front face goes up