grat·is /ˈɡrætəs, ˈɡreɪ-/ adjectiveadj , adverb FREE/COST NOTHINGdone or given without payment 免费的[地] SYN free Medical advice was provided gratis. 医疗咨询是免费提供的。
gratis• Medical advice was provided gratis.
From Longman Business Dictionary
gratisgrat·is /ˈgrætɪs, ˈgreɪtɪs/ adverbadv freeHis work for the charity is performed gratis.
—gratis adjectiveadjThere’s a small charge for some programs; others are gratis.