Tā duì zhè jiàn shì de yìnxiàng yǐjīng hěn dànbó le.
His memory of this event has already grown faint.
Tips
mistakes
Don't confuse with 单薄 (dānbó, 'flimsy / scanty / weak in body') — same pinyin minus the tone slip and a different first character. 淡薄 is about thinness in concentration, intensity or feeling; 单薄 is about thinness in substance or body.
