根据句意，用所给单词的适当形式填空。
“Help _____________(you) to some fish．” Mrs．Black said to her guests．
Although he is in his _____________(ninety), he can do some farm work and look after himself well．
Neil Armstrong took some rock samples for _____________(far) research．
When the parade of Disney characters appeared, all tourists screamed with _______(excited)．
Beijing is in the _____________(north) part of our country．