They are thought to be an important middle size step on the way to building planets.

它们被认为是形成行星的重要中型步骤。

In figure he was not more than of middle size, but was built upon graceful and active lines.

从身材上看， 他不过中等身材， 但体型优美而活泼。

The tailor measured my height and weight; she said I can wear the middle size of that T-shirt.

裁缝测量了我的身高和体重；她说我可以穿那件 T 恤的中号。

Her figure was rather below than above the middle size: It was light and airy as that of an Hamadryad.

她的身材略低于中号， 而不是高于中号：它像 Hamadryad 一样轻盈通风。

So—so it might be that this average middle size is actually ideal to allow this very rare precious thing, which is life, to even happen in a cold, cold, bit of empty space.

所以，这个普通的中等尺寸实际上可能是理想的，可以让这个非常罕见的珍贵东西，也就是生命，甚至发生在一个寒冷的、冰冷的、有点空旷的空间里。

He was a trifle above the middle size, and apparently rather weak in the legs; but this circumstance by no means detracted from his own admiration of his top-boots, which he contemplated, in their elevated situation, with lively satisfaction.

他比中等身材稍大一点，腿部显然很虚弱；但是这种情况丝毫没有减损他对他的高筒靴的钦佩，他在高高的位置上看着这双靴子，非常满意。