■ successful 与 successive

前者是“成功的”，后者是“连续相继的”。

• a successful attempt to land on the moon成功的登月之举
• three successive years of low rainfall连续三年的少雨。

• doubt
• doubt
• doubtful
• doubtful 与 dubious 均可以表示：
• doubt 与 suspect
• dove
• dove 与 pigeon
• down
• downhill
• down south
• down the road
• down your way
• do you think suppose
• do 与 make
• dread
• dreadful
• dread 与 afraid
• dress
• dressmaker
• drive
• drown
• drug
• drunk
• drunken
• drunk 与 drunken