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。

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来重复模仿那个音乐动机。

Five daughters successively entered the world, but yet the son was to come; and Mrs. Bennet, for many years after Lydia's birth, had been certain that he would.

是五个女儿接接连连地出世，儿子还不知道在哪里；丽迪雅出世多少年以后，班纳特太太还一直以为会生儿子。

This enabled the two Voyagers to use a gravity assist technique in which the craft were successively flung from one gassy giant to the next in a kind of cosmic version of crack the whip.

这就使得两艘旅行者号飞船能够利用引力帮助技术，以一种宇宙甩鞭的形式，被从一颗气态巨星连续甩到下一颗气态巨星。