1. The mechanical tissue flakily situated in the downside of the main vein and the bigger lateral veins.
   机械组织成片存在于主脉和较大侧脉靠下表皮侧。
2. The mechanical tissues were mainly composed of fibre, flakily situated in the tops and bottoms of most veins.
   由纤维组成的机械组织，成片存在于绝大多数叶脉的上下方。

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