九年级全一册

- Unit 1：“by + doing sth.”表示“通过做某事”，用来回答“How do you...?”的提问，如“How do you learn English? By reading aloud.”。“be afraid to do sth.”意为“害怕做某事”，“be afraid of (doing) sth.”表示“害怕（做）某事”。

- Unit 5：“be made of...”表示“由……制成”，能看出原材料；“be made from...”表示“由……制成”，看不出原材料。例如“The desk is made of wood.”和“Paper is made from wood.”。