diff --git a/01.geom_line.R b/01.geom_line.R
new file mode 100644
index 0000000..b9962f2
--- /dev/null
+++ b/01.geom_line.R
@@ -0,0 +1,34 @@
+### 模板说明：
+### ggplot2画多变量折线图，共用x轴
+
+
+# 一、最原始办法——手动画每条变量折线
+library(ggplot2)
+
+dat <- data.frame(
+  water_press = c(2, 4, 6),
+  out_volumn = c(1.5, 4, 6),
+  in_volumn = c(1, 3, 5)
+)
+
+pdf("Dr.Liang.pdf", width = 7, height = 5, family = "GB1")
+ggplot(dat) +
+  theme_classic() +
+  geom_point(aes(x = water_press, y = out_volumn, col = "c")) +
+  geom_line(aes(x = water_press, y = out_volumn, col = "c")) +
+  geom_point(aes(x = water_press, y = in_volumn, col = "d")) +
+  geom_line(aes(x = water_press, y = in_volumn, col = "d")) +
+  ggtitle("Dr.Liang 的病生实验") +
+  xlab("水检压计") +
+  ylab("容积变化") +
+  #手动设置图例
+  scale_color_manual(
+    values = c("c" = "#000080", "d" = "#df6100"),
+    name = "变量",
+    labels = c("充气容积", "抽气容积")
+  )
+dev.off()
+
+
+# 二、将dataFrame变为长数据形式后再绘制
+