根据句子意思，用括号中所给单词的适当形式填空，并将答案填写在答题卡的相应位置上。
If you don’t tell me what the problem is, I can’t     (help) you.
Miss Li is a kind teacher and she always talks to us     (gentle).
The teacher told us that the gravity on Mars     (be) only about three-eighth of that on Earth.
Mr Black has been in China for three years and now he is used to      (eat) Chinese food.
The Eiffel Tower, a cultural icon of France, was completed at the end of the      (nineteen) century.
It is worth      (mention) that Nanjing has entered Top 10 Appealing Chinese Cities.