I didn’t see you at the party yesterday.-Oh, I ______ a meeting at that time.

When _______ your mother _______ you that blue dress, Mary-Sorry, I really can’t remember.

It was 80 years before Christopher Columbus crossed the Atlantic______ Zheng sailed to East Africa

It is no good ______ the flowers to often, for alillte water is enough for them.

eople try to knock me down,only me more determined to do better． D．made