I have a lot of trouble making myself understood

句子语法结构分析为

主语+have a lot of trouble (in) doing sth

主语+谓语+宾语+状语结构

主语：I

谓语：have

宾语：a lot of trouble

状语：making myself understood

备注：状语又是一个make +宾语+过去分词（作宾补结构）

句子意思：我有大困难让别人理解我的意思

关于某人有做某事有困难还有以下几种表达

(1)have difficulty (in) doing sth

(2) have trouble (in) doing sth

(3) have problems (in) doing sth 

表示某人艰难做某事还可以这样表达

sb do sth with great difficulty

类结构还有

make oneself heard 是别人听到自己讲话声音