nendo ni kihou ga aru.

subject particle

Breakdown of nendo ni kihou ga aru.

• に: location particle
• ある: to exist/have
• 粘土ねんど: pottery clay

Questions & Answers about nendo ni kihou ga aru.

How do you read 粘土 に 気泡 が ある?

It is read:

ねんど に きほう が ある。

• 粘土（ねんど） = clay
• 気泡（きほう） = air bubble / bubble
• ある = to exist, to be present

So the structure is literally something like:

In the clay, air bubbles exist.

Why is に used after 粘土?

Here, に marks the place where something exists.

With ある and いる, Japanese often uses this pattern:

[place] に [thing] が ある / いる

So:

• 粘土に = in the clay
• 気泡がある = there are bubbles

This is very common:

• 部屋に机がある。 = There is a desk in the room.
• 公園に猫がいる。 = There is a cat in the park.

In your sentence, 粘土に means in the clay or inside the clay.

Why is が used after 気泡?