American schools主語(yǔ)
both public and private對(duì)主語(yǔ)的限定和補(bǔ)充,同位語(yǔ)
consist of謂語(yǔ)
12 years of grades- basically 8 years of eelementary school and 4 years of secondary of high school 賓語(yǔ)
although連詞連接從句
grades 7 and 8, of 7,8 and 9從句主語(yǔ)
may be housed從句謂語(yǔ)（被動(dòng)）
together in a middle school of junior high school從句狀語(yǔ).