adjusting tube（调节管）是什么意思？音标发音+图解场景

调节管 /ɐkˈaʊnt aɪdˈɛntɪfɪkˈeɪʃən/ n

English: adjusting tube · 调节管

释义：Part of the upright into which the vertical tube attached to the horizontal bar slides in order to adjust the height.

这个词出现在以下图解场景（1）