可以购买两种箭了

data/ltw/functions/shop/buy_arrow1.mcfunction

@@ -1,5 +1,6 @@
 # 箭 x2 (1 gi)
 
+execute unless entity @s[scores={shop_arrow=0..}] run scoreboard players set @s shop_arrow 0
 tag @s remove canbuy
 tag @s[scores={shop_arrow=..0,gold=9..}] add canbuy
 

data/ltw/functions/shop/buy_arrow2.mcfunction

@@ -0,0 +1,19 @@
+# 缓慢之箭 x3 (5 gi)
+
+execute unless entity @s[scores={shop_arrow=0..}] run scoreboard players set @s shop_arrow 0
+tag @s remove canbuy
+tag @s[scores={shop_arrow=1,gold=45..}] add canbuy
+
+tellraw @s[scores={shop_arrow=2..}] ["",{"text":">> ","color":"aqua","bold":true},{"text":"你已经购买了这个物品了!","color":"aqua"}]
+tellraw @s[scores={shop_arrow=1,gold=..44}] ["",{"text":">> ","color":"red","bold":true},{"text":"你没有足够的金锭来购买这个物品!","color":"red"}]
+tellraw @s[scores={shop_arrow=..0}] ["",{"text":">> ","color":"red","bold":true},{"text":"你需要先购买上一级的物品!","color":"red"}]
+
+tellraw @s[tag=canbuy] ["",{"text":">> ","color":"green","bold":true},{"text":"你升级到了 缓慢之箭 x3!","color":"green"}]
+scoreboard players add @s[tag=canbuy] shop_arrow 1
+scoreboard players remove @s[tag=canbuy] gold 45
+
+execute as @s[tag=!canbuy] at @s run function lib:sounds/error
+execute as @s[tag=canbuy] at @s run function lib:sounds/levelup
+
+function ltw:shop/refresh_gold
+function ltw:shop/refresh_equip

data/ltw/functions/shop/refresh_equip.mcfunction

@@ -1,4 +1,5 @@
 # 刷新单个玩家购买的物品
 
 clear @s arrow
-give @s[scores={shop_arrow=1}] arrow 2
+give @s[scores={shop_arrow=1}] arrow 2
+give @s[scores={shop_arrow=2}] tipped_arrow{Potion:"minecraft:slowness"} 3