There are some sentences in Japanese that consist of the same word. However, the meaning could be quite different under different auxiliary words, location or tense. Here are some typical examples that you need to be careful.
1. ①なんでもあります vs ②なんでもありません
As shown, one sentence is a positive sentence and the other one is a negative sentence. But the meaning has no connection between them. In Japanese, ① should be translated as “I have everything” or “Everything is here”. In contrast, ② should be translated as “never mind.” Don’t think it as “nothing”.
2. ③あの人は困った人だ vs ④あの人は困っている人だ
Though the tense in these two sentences is different, the meaning they express is exactly the opposite. ③ should be translated as “that person is really a tough guy” or “I really don’t know how to deal with him”. And ④ is saying that “the person is in trouble now”.
3. ⑤私はその薬を三度飲んだ vs ⑥私はその薬を三度で飲んだ
Because of the different auxiliary word, the meaning becomes quite different. ⑤ is saying that “I have taken that medicine for 3 times”. ⑥ is saying that “I divided that medicine into 3 parts and ate it”.
4. ⑦小泉さんは怖い顔をしている vs ⑧小泉さんは怖そうな顔をしている
⑦ means 小泉さん is showing a terrible face. ⑧ means 小泉さん looks like a scary person.