# ETT [GstarCAD 2022](Help%20System/GSTARCAD/2022/Index.md) → [User Guide](Help%20System/GSTARCAD/2022/User%20Guide/(User%20Guide).md) → [Express tool](Help%20System/GSTARCAD/2022/User%20Guide/Express%20tool/(Express%20tool).md) → [GstarCAD Tools](Help%20System/GSTARCAD/2022/User%20Guide/Express%20tool/GstarCAD%20Tools/(GstarCAD%20Tools).md) Normally after extension, the extension effect will be displayed, but ETT command can display the effect in real time until you confirm the position. ## Operation steps: 1. Start the command. 2. Select the line that needs to be extended, the system will choose the nearest side you clicked as extension side automatically . 3. Move the cursor and the segment will extend in real time.