① 定语位置交换：communication problems ↔ problems of communication；silk paper ↔ paper made of silk。
② 主动变被动：environment affects genes ↔ genes are affected by the environment。
③ 代词考察：this / these / those → 先判单复数，再回上一句的主干里找名词。
④ 逻辑关系：类比 look like / resemble；并列 and / too / also；举例 such as 填下义词；否定语义必有直接体现。