main axis的用法和樣例：
例句
- The main stem and fruiting branches of determinant types remain relatively short.
有限生長類型的主莖和果枝仍然較短。 - Subsequent growth of some of the axillaries results in first-order branching of the main stem.
一些腋芽繼續生長形成主莖的第一級分枝。 - The wheel is revolving about its axis.
輪子在軸上轉動。 - By the time the main bout came on.
這時，壓軸賽上場了。
