Through contactguidance to encourage children's creation and performance.
通过隐形指导鼓励幼儿的创造与表现。
2
Single-direction and double-direction angular contact thrust ball bearings (Figures 1.50 and 1.51) are used for machine tool spindles requiring rigid axial guidance.
单向和双向推力角接触球轴承（图1.50和1.51）都用机床主轴轴向刚性作为指导。
3
To discuss an alternative approach, contact the FDA staff responsible for this guidance as listed on the title page.