Alternatively, the plants can grow with their roots in a substratum such as sand, vermiculite, or LECA granules.

除之外，植物也可以在土壤中生长，如沙子、蛭石或莱卡颗粒。

In this there was a substratum of truth.

这里面有一个真理的基础。

Firmly narrowing upward from this wealthy but inconspicuous substratum was the compact and dominant group which the Mingotts, Newlands, Chiverses and Mansons so actively represented.

从这个富有但不显眼的底向上缩小的是明戈特、纽兹、奇弗斯和曼森家族如代表的紧凑而占主导地位的群体。

Mr Chivers overlays a street map with colours representing the different substrata - " half eccentric artwork, half primary-school science project" - which becomes a springboard for his digressions.

奇弗斯先生用代表不同底结构的不同颜色，描绘出一张街道地图——“既像古怪的艺术品，又像小学的科学项目”——这成了他离题的跳板。

While he did not answer she began to feel the old hypnotism of his intelligence, sometimes exercised without power but always with substrata of truth under truth which she could not break or even crack.

虽然他没有回答，但她开始感受到他智慧的古老催眠术，有时没有力量，但总是在真理之下隐藏着真理的底，她无法打破甚至破解。