Bacterial means “of bacteria” or “caused by bacteria.” Bacteria are tiny living things, too small to see, that live on skin, in soil, in food, and inside our bodies. Some help us, like the ones in the gut; some make us ill.

Bacterial這個字 means意思是 "of bacteria"「細菌的」 or或 "caused by bacteria."「由細菌引起的」。Bacteria細菌 are是 tiny living things微小的生物，too small to see小到看不見，that live on skin, in soil, in food, and inside our bodies生活在皮膚上、土壤裡、食物中，以及我們體內。Some有些 help us對我們有幫助，like the ones in the gut像是腸道裡的那些；some有些 make us ill則會讓我們生病。

So a bacterial infection is an illness those tiny lives started — some sore throats, some food poisoning, some skin problems.

So所以 a bacterial infection細菌感染 is an illness就是...的疾病 those tiny lives started那些微小生物引起——some sore throats有些是喉嚨痛，some food poisoning有些是食物中毒，some skin problems有些是皮膚問題。

Doctors often set this word next to “viral”: a viral cold will not get better with antibiotics, but a bacterial one might.

Doctors醫生 often set this word next to "viral"常常把這個字和「viral（病毒的）」放在一起講：a viral cold病毒引起的感冒 will not get better with antibiotics不會因為抗生素而好轉，but但 a bacterial one細菌引起的感冒 might可能會。

It is a school-and-hospital adjective, a little formal, and it always points back to those tiny living things, not to a feeling or a fashion.

It這個字 is是 a school-and-hospital adjective常見於學校和醫院的形容詞，a little formal有點正式，and而且 it它 always points back to總是指向 those tiny living things那些微小的生物，not to不是指 a feeling or a fashion一種感覺或流行。