灰塵: ash and dust; something worthless / 灰燼: ash and cinders / 怪人: someone mysterious (in a negative way) / 芥塵: trash, rubbish / 海人: someone who lives by the sea; a fisherman or fisherwoman

回文: palindrome

貝類: shellfish

海流: (oceanic) current

開催: holding a conference or event

scallop mantle (as a food)

徴収: levy / 徴集: recruitment / 聴衆: audience, attendance

論集: a collection of essays or treatises

イリノイ州: Illinois, a state of the United States of America. Capital: Springfield. Largest city: Chicago.

吸収: suction, absorption / 旧習: (rare) old customs / 急襲: (rare) raid