"如果一个老师知识渊博,那么他所说的话就会更有信服力"请问这句话可以这么说吗?(如不合适请帮忙改正)
if a teacher is source of knowledge, then the students would like to obey her advice.

如果在你的基础上修改的话，保证无语法错误别人看得明白就行（第一步），至于词语的选择也会影响句子的精确性（第二步）：
(1)if a teacher has great sources of knowledge, the students would like to take his advice.

(2)A teacher who has a great source(s) of knowledge can make his students take his advice.

(3)A teacher who has a great source(s) of knowledge can convince his students of his words.

(4)A teacher who is knowledgable can (fully) convince his students of his words
四个句子逐渐修改的，最后两个个可能简洁一些，也更有说服力．定语从句修饰教师，更强调后面的事实．翻译就是这样，要仔细推敲．其次语言点的运用也要恰当，convince sb of sth.