总结时遇到的几个语法问题

tbs

1.less of +名词,表示较少部分,其中这个名词是可数不可数都行的吗?看到一个句子:because natural gas is composed mostly of methane,a simple hydrocarbon, vehicles pwoered by natural gas emit(less of certaim pollutants than those burning gasoline or diesel fuel.)

2.have an impact 后面只可以加on sth.不能加to sth 吗?

3.Byron possessed pwoers of observation that would have made him a great anthropologist and that (make his letters as a group the rival of )the best novels of the time.
想问一下the rival of ....与as a group语法上什么关系?the rival 是名词,a group 也是名词,又不像同位语??不太明白

4.有没有A is three times larger than B 的说法?有的话,用数学表达式表示是A=3B吗?还是A=4B?语法看的我数学都疑神疑鬼了.

谢谢谢谢谢谢!!!!!!!

tbs

哦,谢谢你,可是我刚检查了一下,除了power打错了其他时态没问题,3是刘振民书283页T2-11