So can the movement of aphids when, having depleted the young leaves on one food plant, their offspring then fly onward to a different host plant, with no one aphid ever returning to where it started.

蚜虫的运动也是如此，当吃完一株食用植物的幼叶，它们的后代会飞到另一株宿主植物上，没有蚜虫会再回到最初的地方。

youdao

He still walked onward, if that movement could be so described, which rather resembled the wavering effort of an infant, with its mother's arms in view, outstretched to tempt him forward.

他还继续朝前“走”着——如果我们还把那种动作说成是“走”的话，其实更象一个婴儿看到了母亲在前面伸出双手来鼓励自己前进时那种播摇晃晃的学步。

youdao