Occasions are quite rare ________ I have time to spend a day with my kids.
---I’m afraid I must be off now . --- ____________________ .
The company has turned ____ e-commerce.
The enemies tried to ____ the city, but they failed in the end.
Japan is ____ the east of China, while India is ____ the west of China.
It was stupid ____ him for help. Everyone knows that he is very mean.