“Readers of the book Thresholds will experience what Glenna Cook calls ‘the good purpose,’ the intention of poems meaningfully conflicted between fierce moments and tender moments that compose a life. In all her wisdom and experience, she still struggles to answer questions about love, devotion, loneliness and ‘this grandeur of the universe.’ These carefully constructed poems share childhood pains and shames. Like any poet, Cook plays subordinate to language: ‘I’m sorry/about my words./I try to keep them in/behind their white picket fence,/but they...