I remember _________ the doors when I left the house, but I forgot _______ you about that so that you didn’t need to worry.
Now that spring is here, you can ______ these fur coats till you need them again next winter.
Up to now, the program ______ thousands of children who would otherwise have died.
Mark needs to learn Chinese ______ his company is opening a branch in Beijing.
Paper money was in ____ use in China when Marco Polo visited the country in ____ thirteenth century.
----I’m sorry I made a mistake ! ----_______. Nobody is perfect .