对于大部分同学们来说，托福写作难度系数是比较高的，导致很多同学对于托福写作自信不足，今天就和小编来看看托福写作核心词组一览。

　　1.a couple of 两三个，几个
　　Although he thought of the key idea in 1951, the first maser was not completed until acouple of years later.

　　2. account for 解释
　　Variations of clay composition and the temperatures at which they are fired account forthe differences in texture and appearance.

　　3. adapt to 使适应于
　　They have been able to adapt to ecological changes.

　　4, adorn with sth 用…装饰
　　Some pots were adorned with incised or stamped decorations.

　　5.appeal to 吸引
　　Publishing literature consisting of exciting stories that would appeal to both childrenand adults

　　6.apply to 适用于
　　Ethological theory began to be applied to research on children in the 1960’s.

　　7.at best 充其量，最多
　　Hunting is at best a precarious way of procuring food, even when the diet issupplemented with seeds and fruits.

　　8.at intervals 相隔一定距离
　　However, at intervals of 10 to 100 years, these glaciers move forward up to 100 times faster than usual.

　　9.at the expense of sth 在损害…的情况下
　　A multitude of microorganisms make their livings directly at the expense of othercreatures.