共 + Verb + Number + Measure Word
共 (gòng) means "total," "altogether," or "in all." It is an adverb placed before a verb to indicate the total amount or sum of something. It is often interchangeable with 一共 in spoken Chinese.
我们班共有三十五个学生。
wǒmen bān gòng yǒu sānshíwǔ gè xuéshēng.
Our class has a total of thirty-five students.
这次活动共花了两万块钱。
zhè cì huódòng gòng huā le liǎng wàn kuài qián.
This event cost a total of twenty thousand yuan.
他在这家公司共工作了十二年。
tā zài zhè jiā gōngsī gòng gōngzuò le shí'èr nián.
He worked at this company for a total of twelve years.