1 . 选择并使用所给英语单词的正确形式完成句子,有两个单词为多余词。

challenge，depend，profession，argue，adult，flexible，normal

1. He had an ____________ with the researcher on experimenting on animals.
2. The extreme weather is regarded as ___________ for March in this area.
3. Living alone in a foreign country is ___________ for most people.
4. We plan to invite ___________ writers to give talks on story writing.
5. Teenagers are looking forward to being _____________ of their parents.