1. Tigers are one of the most amazing animals on Earth! They are big, powerful cats with striking orange and black striped fur.

2. Tigers are the biggest cats in the whole world.

3. They have 4 legs and a big head.

4. Tigers are very strong.

5. Tigers have beautiful furs.

这些句子简洁明了地描述了老虎的外貌特征，适合三年级学生使用。