N2 — outside your level filter
write + doesn't even — marks that even a minimal, expected act didn't happen, against a backdrop of contrast
kaki mo shinai
doesn't even — marks that even a minimal, expected act didn't happen, against a backdrop of contrast
meaning: not even write
あれほど世話になったのに、お礼の手紙を書きもしない。
are hodo sewa ni natta noni, orei no tegami o kaki mo shinai.
Despite all he'd done for me, I not even write a thank-you letter. neutral
あれだけ迷惑をかけたのに、あいつは謝りもしない。
are dake meiwaku o kaketa noni, aitsu wa ayamari mo shinai.
After causing all that trouble, that guy won't even apologize. casual