2. (solid) body frame.

3, (hard) body frame.

4. (strong) body frame.

5. (solid) frame.

Definition of words:

1, firm, pronounced as jiān tǐng, a Chinese word, meaning hard, hard and straight.

2, stable, is a Chinese character, pinyin is jiān shí, which means that the structure is good, the position is consolidated, and there is no gap for the other party to take advantage of.

3, hard work, pronounced Ji ā nyxing, a Chinese word, means hard work.