主謂一致的三條原則
1）語(yǔ)法一致原則。主語(yǔ)是單數(shù)，謂語(yǔ)動(dòng)詞用單數(shù)形式；主語(yǔ)是復(fù)數(shù)，謂語(yǔ)動(dòng)詞用復(fù)數(shù)形式。
【例如】
My friend has no intention of going shopping with me.
My friends have no intention of going shopping with me.
2）意義一致原則。主語(yǔ)和謂語(yǔ)的一致不是由主語(yǔ)的語(yǔ)法形式來(lái)決定，而是由主語(yǔ)所表達(dá)的意義決定。
【例如】
The class are busying writing English passages.
The United States is a developed country which has advanced science and technology.
帶有復(fù)數(shù)詞尾的學(xué)科名稱、國(guó)家等在意義是表示單數(shù)概念，用單數(shù)動(dòng)詞。
3）就近原則。謂語(yǔ)動(dòng)詞的單、復(fù)數(shù)取決于最靠近它的主語(yǔ)。由either...or，neither...nor，not only...but also連接或由here，there等引導(dǎo)的句子，謂語(yǔ)動(dòng)詞遵循這一原則。
【例如】Neither my friends nor I was able to persuade him to accept our advice.
Either he or she has broken the window, for there is no one else there.
There is a teacher and fifty students in the classroom.