.A cook will be immediately fired if he is found _____ in the kitchen.
Drivers must stop when the traffic lights _____ red.
There was an excited expression ______ his face when he heard the good news.
Milk will turn sour soon on hot days ______ it is stored in the refrigerator.
You'd better not ride the bicycle on snowy days; you ______ fall.
—Hi, Jack.You look a bit fat now. —Yes, I ______ five pounds recently.