在箱线图中显示均值，并绘制折线图

Question

有两个问题与通过箱线图和线图（图形）表示数据有关，我需要帮助。

1. 使用下面提供的数据，我如何以附加图像中表达的方式显示我的结果？

我希望保留因变量“C2.dn”在 y 轴上，并保留变量“辅音”在 x 轴上，“方式”以显示对列。

2. 如何将观测值的平均值与显示中值的水平黑条一起用箱线图表示？

在代码中：

boxplot(C2.dn ~ Consonant + Manner, data = df)

最少数据：

structure(list(Filename = c("AK_baga.TextGrid", "AK_bagga.TextGrid", 
"AK_chape.TextGrid", "AK_chappe.TextGrid", "AK_fati.TextGrid", 
"AK_fatti.TextGrid", "AK_gada.TextGrid", "AK_gadda.TextGrid", 
"AK_kala.TextGrid", "AK_kalla.TextGrid", "AK_katha.TextGrid", 
"AK_kute.TextGrid", "AK_kutte.TextGrid", "AK_manni.TextGrid", 
"AK_rami.TextGrid", "AK_rammi.TextGrid", "AK_sada.TextGrid", 
"AK_saka.TextGrid", "AK_sakka.TextGrid", "AK_sune.TextGrid"), 
Consonant = c("Singleton", "Geminate", "Singleton", "Geminate", 
"Singleton", "Geminate", "Singleton", "Geminate", "Singleton", 
"Geminate", "Singleton", "Singleton", "Geminate", "Geminate", 
"Singleton", "Geminate", "Singleton", "Singleton", "Geminate", 
"Singleton"), Manner = c("Stop", "Stop", "Stop", "Stop", 
"Stop", "Stop", "Stop", "Stop", "Liquid", "Liquid", "Stop", 
"Stop", "Stop", "Nasal", "Nasal", "Nasal", "Stop", "Stop", 
"Stop", "Nasal"), C2_xsampa = c("g", "g:", "p", "p:", "t`", 
"t`:", "d_d", "d_d:", "l", "l:", "t_d_h", "t_d", "t_d:", 
"n:", "m", "m:", "d_d", "k", "k:", "n"), C2.dn = c(5.1590675, 
15.0333214, 8.0042611, 16.4554347, 8.422198, 15.216855, 7.9476419, 
14.4379144, 7.0444361, 16.5907065, 8.7118953, 7.3607761, 
19.7175146, 14.5908118, 8.6481358, 14.1979702, 8.0666696, 
8.2999095, 20.1309756, 6.5158316)), class = "data.frame", row.names = c(NA, 
-20L))

任何帮助将不胜感激。