Make a rough sketch before you draw.

画画得先打个底子。

《新英汉大辞典》

Use your Lasso to draw a rough selection around your image.

使用套索在你的图像周围画一个粗略的选区。

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Or as shown below, you might simply draw the rough boxes on a page to show where you want to display different information, include drop boxes and so forth.

或者如下所示，仅仅画出粗略的框图，标明在哪儿显示什么信息，包括下拉列表等等。

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To keep costs down, Mr. Breaux used an architect only to draw rough plans and he didn't hire an interior designer.

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