“叶脉”造句

杂草中危害通常仅限于叶脉间的条状区域.
On grasses, injury is usually confined to areas between the veins.

叶脉有两种:平行脉和网状脉.
There are two kinds of venation , parallel and net.

叶脉中木质部比重越大,越有利于水分的传输.
Large proportion of xylem benefit to the water transfer.