Use thick lines.

使用粗线。

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When the researchers dissected these now susceptible mice, they discovered that the mucous layer that typically lines the gut was only half as thick as in protected mice.

当研究人员解剖这些现存的易感染的小鼠时，他们发现其肠道典型的线性分泌粘液层的厚度仅为受保护小鼠的一半。

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The appended drawings shall be made in black ink with the aid of drafting instruments. The lines shall be uniformly thick and well-defined, and shall not be altered.

附图应当用制图工具和黑色墨水绘制，线条应当均匀清晰，并不得涂改。

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He draws pencil sketches, knowing that all lines must connect, and not be too thick or thin.

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Until they were pulled back from most of the squares and the street corners in the city centre a couple of days ago, there were long lines of riot police, revolutionary guards and 'basijis' - militia men mainly armed with thick wooden clubs.

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