kono kikai o atsukau.

I handle this machine.

Breakdown of kono kikai o atsukau.

• を: direct object particle
• この: this
• 機械きかい: machine
• 扱あつかう: to handle; treat

Questions & Answers about kono kikai o atsukau.

What does この mean here, and why is it not これ?

この means this and must be followed by a noun, so この機械 means this machine.

By contrast:

• これ = this one / this thing
• この + noun = this ...

So:

• これを扱う。 = Handle this.
• この機械を扱う。 = Handle this machine.

Why is there a を after 機械?

The particle を marks the direct object of the verb. In other words, it shows what is being handled or operated.

Here:

• 機械 = machine
• 機械を = the machine / machine as the thing being acted on
• 扱う = to handle, deal with, operate

So 機械を扱う means to handle/operate the machine.

What is the reading of 機械 and 扱う?

The reading is:

• 機械 → きかい
• 扱う → あつかう

So the full sentence is read:

この きかい を あつかう。