Point out the parts of speech of the underlined words.( 指出下列句中画线的词类。 ) 1. The teacher with two of his students is walking into the classroom . 2. There is an old man coming here . 3. The useful dictionary was given by my mother last year . 4. To do today's homework without the teacher's help is very difficult . 5. I don't like the picture on the wall .