【何等】文言文遗留，现在人们都能听懂，但是一般用【多么】代替。 【未曾】文言文，现在人们都能听懂，基本不使用。同义词是【没有】【从来没有】 【慈爱】书面使用。口语用近义词【慈祥】。

hello I want to learn English Can you teach me I can speak Chinese

i personally think they aren't that common words, at least i wouldn't use them that often when i have some chitchat with my friends. ;p yes mostly you might seee them in some literature works,but i guess not only bible. ;p 慈爱 is relatively the best common word among them, maybe because its an adjective,you can use it to describle what a person is like. 何等and 未曾 sound more like ancient chinese. of course you definitely could use them in your written chinese.that may make your writing a bit special from others. ;D Btw i do get into the way of asking one word or phrase is used often whenever i get to learn some new ones, just like you. i really don't want to occupy my memory capacity for those less-than-common ones considering my current englsih level. ;p Hope my answer would offer some help. ;p

we usually use these words in written.if we use them when we speak,it sounds very weird.