缺少谓语
They are sometimes noisy
【1】sometimes可以放在句首,作状语,表示时间,修饰整个句子.如:Sometimes we go to the cinema.
【2】sometimes 还可以放在主语后面动词前面,如:He sometimes comes to see me.但如果这个动词是系动词(are),就要放在系动词后面,如本句.
缺少谓语
They are sometimes noisy
【1】sometimes可以放在句首,作状语,表示时间,修饰整个句子.如:Sometimes we go to the cinema.
【2】sometimes 还可以放在主语后面动词前面,如:He sometimes comes to see me.但如果这个动词是系动词(are),就要放在系动词后面,如本句.