与えられた文字列中に含まれる単語の個数を単語ごとにカウントする for Powershell

wc.ps1

$s = "I have a pen. I have a apple. oh!! Apple pen! I have a pen. I have a pineapple. oh!! Pineapple pen! Apple pen. Pineapplepen. Pen pineapple apple pen."
$s -split(' ') | ?{ $_ -match "(\w+)[^.!]?" } | %{ $matches[1] } | group | select -Property Name,CountName   

# Name         Count
# ----         -----
# I                4
# have             4
# a                4
# pen              7
# apple            4
# oh               2
# pineapple        3
# Pineapplepen     1