Question

Steve has done his homework ________, but Kathy hasn't done hers ________.

1. A.
   already, yet
2. B.
   already, already
3. C.
   yet, yet
4. D.
   yet, already

Answer 1

A
already和yet都有“还，直到现在还”之意，一般用于现在完成时态already一般用于肯定句，yet一般用于否定句和疑问句；ever“曾经”；never“从来没有”。