These layers are slowly and successively produced by the animal itself.

这一层一层的物质都是住在贝壳里的牡蛎自己生成的。所以，珍珠形成得十分缓慢。

During their stay, two lab modules, Wentian and Mengtian, will be sent successively into space.

在飞船停留在太空的期间，问天和梦天两个实验舱模块将先后被送入太空。

Melodic sequence is simply the repetition of a musical motive at a successively higher or lower degree of the scale.

旋律模进只是在音阶的高几度或低几度的位置来重复模仿那个音乐动机。

Without realising it, he saw all the rays of the twilight become successively extinguished.

不知不觉间， 他看到那暮光之中， 所有的光芒都接连熄灭。

Next time, we'll discuss other kinds of writing successively.

下次，我们将依次讨论其他类型的写作。

All was hushed, till the general stillness was again disturbed by the groaning, which was repeated several times successively.

一切都安静下来， 直到呻吟声再次打破了一般的寂静， 呻吟声连续重复了好几次。

Many different commodities, it is probable, were successively both thought of and employed for this purpose.

很可能，许多不同的商品相继被想到并用于此目的。

After that, the talented Miss Cowley drove successively a trade delivery van, a motor-lorry and a general!

之后，才华横溢的考利小姐先后驾驶了一辆贸易货车、一辆机动货车和一名将军！

Julien approached successively the several groups and attracted no attention by reason of his lack of importance.

于连先后走近几群人， 因为他不重要， 所以没有引起注意。

Then the next higher, and the next would be successively filled, and the lowest would be the last to vanish.

然后是下一个更高的， 下一个将依次被填充， 最低的将最后消失。