$scoreboard players add @s gems_to_add $(amount)
$execute if score @s gems_to_add matches 1 run tellraw @s {"text":"+$(amount) Gem","color":"green"}
$execute if score @s gems_to_add matches 2.. run tellraw @s {"text":"+$(amount) Gems","color":"green"}
tag @s remove attacker
tag @s remove bow_attacker