1. All appeals filed by the Defendant (Counterclaim Plaintiff) against the principal lawsuit and counterclaim are dismissed.

2. All costs of appeal.

1. The grounds for appeal concerning the defendant's principal lawsuit and counterclaim as to the judgment of the court of first instance are not significantly different from the allegations in the court of first instance, and even if the evidence submitted in the court of first instance shows each evidence submitted in this court, the fact-finding and judgment of the court of first instance are justified.

Therefore, the reasoning of the judgment of this court is identical to the reasoning of the judgment of the first instance except for the addition or dismissal in the following two paragraphs, and thus, it is acceptable in accordance with the main sentence of Article 420 of the Civil Procedure Act.

2. Following the 7th page of the 7th judgment of the court of first instance, the part added or heighted “no objection has been raised.” On May 22, 2017, when the contract for the temporary materials lease of this case was in progress, the Defendant and C drafted a letter of undertaking to assume 50% of the Plaintiff and the Defendant and C’s 25% of the injury incurred to the Plaintiff at the site (Evidence B No. 8), and if the Plaintiff is either a sub-subcontracted illegal re-subcontract or a construction company under C’s direction, the Defendant added the above letter of undertaking without any reason.

The 5th 10, 14, 19, 7th 10, 8th 5, and 16th 16 of the judgment of the court of first instance shall be considered as the "direct pumps (the part which was reconstructed due to manufacturing errors, etc. after the installation process of the relevant system vision)".

Paragraph 1 of Paragraph 1 of the 9th judgment of the first instance court "limited to labor expenses" is regarded as "labor expenses".

3. The judgment of the court of first instance is just, and the defendant's appeal on the main lawsuit and counterclaim is without merit, and all of the appeals are dismissed. It is so decided as per Disposition.