Pour the materials onto the base and use the rubber scratch board to make the surface flat and make the bottom materials permeate into the cement base. Do not leave some areas unpainted.

将物料倒于基面，用橡胶刮板刮平，要求不得漏涂，使底料渗透于水泥基层中。

youdao

His early prototype takes a few cues from Boogie Board's line of scratch pads.

ENGADGET

Peterffy had taken the incoming data wire meant for the terminal and spliced it, soldering the split end into a circuit board that his team of programmers and physicists had built from scratch and embedded into the motherboard of an IBM PC.

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