"about math, research papers, science"

"坐在坦克上的哈士奇"

"靠着罗马柱睡觉的大胡子男人"

"睡在一只白猫肚子上的小老鼠"

"Mermaid with a magical harp"

"Viking with a helmet and axe"

"Wizard with a mystical orb"

"Alien with a laser gun"

"Sorceress with a crystal ball"

"Steampunk clockwork machine"

"Viking warrior with an axe"

"Haunted mansion on a hill"

"Witch’s cauldron bubbling"