7. (5 points)
Grandma's eyesight is poor, and she accidentally put soy sauce in the vinegar bottle, put cooking wine in the soy sauce bottle, put oil in the cooking wine bottle, and put vinegar in the oil bottle. Xiao Fei used an empty bottle to help Grandma put these seasonings back into the correct bottles. Xiao Fei poured the seasonings at least $\qquad$ times.
$5$