export function normalizeVocabAnswer(s) { return String(s || '').trim().toLowerCase().replace(/[^a-z0-9'-]/gi, '') } export function escapeRegExp(s) { return String(s).replace(/[.*+?^${}()|[\]\\]/g, '\\$&') } export function exampleWithBlank(word) { if (!word?.example) return '' const re = new RegExp(`\\b${escapeRegExp(word.word)}\\b`, 'gi') return word.example.replace(re, '_____') }