根据句意和汉语提示写出单词，完成句子。每空一词。
I think          (语法) is the most difficult part in English study.
Columbus(哥伦布)         (发现) AmericaContinent in 1492.
We never           (怀疑) that they can learn English well through their hard work .
Lily got full           (分数) in English test because of her hard work.
It’s time for the player to drink to his            (胜利).