kono kikai no sousa ga wakaranakereba, tenin ni kiite kudasai.

subject particle

Breakdown of kono kikai no sousa ga wakaranakereba, tenin ni kiite kudasai.

• の: possessive case particle
• に: indirect object particle
• この: this

Questions & Answers about kono kikai no sousa ga wakaranakereba, tenin ni kiite kudasai.

What does この mean here, and what is it modifying?

この means this and directly modifies 機械 (machine), so この機械 means this machine.

In Japanese, この must be followed by a noun. So:

• この機械 = this machine
• この by itself is not enough

If you wanted this one, you would use これ instead.

Why is there a の between 機械 and 操作?

The の links the two nouns together.

• 機械 = machine
• 操作 = operation / use / handling

So 機械の操作 means something like:

• the operation of the machine
• how to use the machine
• the machine’s operation

This noun + の + noun pattern is extremely common in Japanese.

Why is it 操作が分からない and not 操作を分からない?

Because 分かる does not usually take を for the thing understood. It commonly uses が.

So:

• 操作が分かる = understand the operation / know how to use it
• 操作が分からない = do not understand the operation / do not know how to use it

This feels unusual to English speakers because English uses a direct object: understand something. But Japanese treats the thing understood as the thing that is understandable / becomes clear, so が is natural.