All of your reasons are on the base of support that you hypothesized first.

你的所有理由全部基于你的假设.

互联网

Enlarge your base of support, placing feet apart.

.分开两腿,扩大支撑基础.

互联网

In this way, the legs become a firm base of support for the spine.

通过这种方式, 双腿成为脊柱稳定的根基.

互联网