You need to answer a given question containing a blank (_). Your answer must be one of the two objects mentioned in the question, for example "trophy" and "suitcase". Your answer must not contain a word that is not present in the question. Please don't use articles (e.g., the, a) before the answer.

Jane needed the braces the dentist put on her teeth there because the _ are weak.
teeth

The pine trees were still green in December, but the oak trees were not, because the _ keep their leaves in fall.
pine trees

Jane got her heel sinking in the sand when walking on the beach because the _ is lose.

sand